Tag Archives: Nuclear Weapons

U.S. test-fires ICBMs to stress its power to Russia, North Korea

VANDENBERG AIR FORCE BASE, Calif. (Reuters) – The U.S. military test-fired its second intercontinental ballistic missile in a week on Thursday night, seeking to demonstrate its nuclear arms capacity at a time of rising strategic tensions with Russia and North Korea.

The unarmed Minuteman III missile roared out of a silo at Vandenberg Air Force Base in California late at night, raced across the sky at speeds of up to 15,000 mph and landed a half hour later in a target area 4,200 miles away near Kwajalein Atoll in the Marshall Islands of the South Pacific.

Deputy Defense Secretary Robert Work, who witnessed the launch, said the U.S. tests, conducted at least 15 times since January 2011, send a message to strategic rivals like Russia, China and North Korea that Washington has an effective nuclear arsenal.

“That’s exactly why we do this,” Work told reporters before the launch.

“We and the Russians and the Chinese routinely do test shots to prove that the operational missiles that we have are reliable. And that is a signal … that we are prepared to use nuclear weapons in defense of our country if necessary.”

Demonstrating the reliability of the nuclear force has taken on additional importance recently because the U.S. arsenal is near the end of its useful life and a spate of scandals in the nuclear force two years ago raised readiness questions.

The Defense Department has poured millions of dollars into improving conditions for troops responsible for staffing and maintaining the nuclear systems. The administration also is putting more focus on upgrading the weapons.

President Barack Obama’s final defense budget unveiled this month calls for a $1.8 billion hike in nuclear arms spending to overhaul the country’s aging nuclear bombers, missiles, submarines and other systems.

The president’s $19 billion request would allow the Pentagon and Energy Department to move toward a multiyear overhaul of the atomic arms infrastructure that is expected to cost $320 billion over a decade and up to 1 trillion dollars over 30 years.

The nuclear spending boost is an ironic turn for a president who made reducing U.S. dependence on atomic weapons a centerpiece of his agenda during his first years in office.

Obama called for a world eventually free of nuclear arms in a speech in Prague and later reached a new strategic weapons treaty with Russia. He received the Nobel Peace Prize in part based on his stance on reducing atomic arms.

“He was going to de-emphasize the role of nuclear weapons in U.S. national security policy … but in fact in the last few years he has emphasized new spending,” said John Isaacs of the Council for a Livable World, an arms control advocacy group.

Critics say the Pentagon’s plans are unaffordable and unnecessary because it intends to build a force capable of deploying the 1,550 warheads permitted under the New START treaty. But Obama has said the country could further reduce its deployed warheads by a third and still remain secure.

Hans Kristensen, an analyst at the Federation of American Scientists, said the Pentagon’s costly “all-of-the-above” effort to rebuild all its nuclear systems was a “train wreck that everybody can see is coming.” Kingston Reif of the Arms Control Association, said the plans were “divorced from reality.”

The Pentagon could save billions by building a more modest force that would delay the new long-range bomber, cancel the new air launched cruise missile and construct fewer ballistic submarines, arms control advocates said.

Work said the Pentagon understood the financial problem. The department would need $18 billion a year between 2021 and 2035 for its portion of the nuclear modernization, which is coming at the same time as a huge “bow wave” of spending on conventional ships and aircraft, he said.

“If it becomes clear that it’s too expensive, then it’s going to be up to our national leaders to debate” the issue, Work said, something that could take place during the next administration when spending pressures can no longer be ignored.

(Reporting by David Alexander; Editing by Jonathan Oatis and John Stonestreet)

China urges North Korea, U.S. to hold direct talks

BEIJING (Reuters) – China’s foreign ministry on Monday urged the United States and North Korea to sit down with each other face-to-face and resolve their problems, as tension continues to climb on the Korean peninsula after North Korea’s latest rocket test.

While China was angered by the launch, it has also expressed concern at plans by Washington and Seoul to deploy an advanced U.S. missile defense system, saying it would impact upon China’s own security.

“The focus of the nuclear issue on the peninsula is between the United States and North Korea,” Chinese Foreign Ministry spokesman Hong Lei told a daily news briefing.

“We urge the United States and North Korea to sit down and have communications and negotiations, to explore ways to resolve each other’s reasonable concerns and finally reach the goal we all want reached.”

North Korea launched a long-range rocket on Feb. 7 carrying what it called a satellite, drawing renewed international condemnation just weeks after it carried out a nuclear bomb test.

It said the launch was for peaceful purposes, but Seoul and Washington have said it violated United Nations Security Council resolutions because it used ballistic missile technology.

North Korea’s nuclear bomb test last month was also banned by a U.N. resolution.

China, while frustrated by North Korea and having signed up for numerous previous rounds of United Nations sanctions on its isolated neighbor, has said it does not believe sanctions are the way to resolve the problem and has urged a return to talks.

Numerous efforts to restart multilateral talks have failed since negotiations collapsed following the last round in 2008.

Chinese popular opinion has become increasingly fed up with North Korea, a country once a close diplomatic ally.

In an editorial on Monday, the official English-language China Daily called for new U.N. sanctions to “truly bite”.

“The threat of a nuclear-armed DPRK is more real than ever,” it said, using the North’s formal name, the Democratic People’s Republic of Korea.

Hong repeated that North Korea would have to “pay a price” for its behavior.

Tension persists on the Korean peninsula.

Last Wednesday, South Korea suspended operations at the Kaesong industrial zone just inside North Korea, as punishment for the rocket launch and nuclear test.

The North on Thursday called the action “a declaration of war” and expelled the South’s workers. Kaesong, which had operated for more than a decade, was the last venue for regular interaction between the divided Koreas.

Asked about the zone’s shutdown, Chinese spokesman Hong said the peninsula was in a “complex and sensitive” phase.

“We hope all sides can take steps to ameliorate the tense situation,” he said.

(Reporting by Ben Blanchard; Editing by Clarence Fernandez)

North Korea may get plutonium from restarted reactor in weeks, U.S. says

WASHINGTON (Reuters) – North Korea, which conducted its fourth nuclear test last month and launched a long-range rocket on Saturday, could begin to recover plutonium from a restarted nuclear reactor within weeks, the director of U.S. National Intelligence said on Tuesday.

James Clapper said that in 2013, following its third nuclear test, North Korea announced its intention to “refurbish and restart” facilities at its Yongbyon nuclear complex, to include the uranium enrichment facility and its graphite-moderated plutonium production reactor shut down in 2007.

“We assess that North Korea has followed through on its announcement by expanding its Yongbyon enrichment facility and restarting the plutonium production reactor,” Clapper said in prepared testimony to the Senate Armed Services Committee.

“We further assess that North Korea has been operating the reactor long enough so that it could begin to recover plutonium from the reactor’s spent fuel within a matter of weeks to months,” he said in his annual Worldwide Threat Assessment.

North Korea has used its graphite-moderated reactor at Yongbyon as a source of plutonium for its atomic bombs. It tested a fourth nuclear device on Jan. 6.

North Korea said in September that Yongbyon was operating and that it was working to improve the “quality and quantity” of weapons which it could use against the United States at “any time.”

Clapper said North Korea’s nuclear weapons and missile programs would “continue to pose a serious threat to U.S. interests and to the security environment in East Asia in 2016.”

He said North Korea had expanded the size and sophistication of its ballistic missile forces and was also “committed to developing a long-range, nuclear-armed missile that is capable of posing a direct threat to the United States.”

Clapper said Pyongyang had publicly displayed a road-mobile intercontinental ballistic missile, or ICBM, on multiple occasions, and the U.S. assessment was that it had taken initial steps toward fielding the system, although it had not been flight-tested.

North Korea said that it launched a satellite into space on Saturday with a long-range rocket. The United States and its allies see the launch as cover for Pyongyang’s development of ballistic missile technology that could be used to deliver a nuclear weapon.

The launch was strongly condemned by the United States, its allies and the United Nations Security Council.

(Reporting by David Brunnstrom; Editing by Jonathan Oatis)

U.S. and allies aim to track North Korean rocket launch

SEOUL/TOKYO (Reuters) – The United States has deployed missile defense systems that will work with the Japanese and South Korean militaries to track a rocket North Korea says it will launch some time over an 18-day period beginning Monday.

China, the North’s sole major ally but opposed to Pyongyang’s nuclear program, appealed for calm.

North Korea has notified U.N. agencies it will launch a rocket carrying what it called an earth observation satellite some time between Feb. 8 and Feb. 25, triggering international opposition from governments that see it as a long-range missile test.

North Korea says it has a sovereign right to pursue a space program. But it is barred under U.N. Security Council resolutions from using ballistic missile technology.

Coming so soon after North Korea’s fourth nuclear test, on Jan. 6, also barred by Security Council resolutions, a rocket launch would raise concern that it plans to fit nuclear warheads on its missiles, giving it the capability to strike South Korea, Japan and possibly the U.S. West Coast.

China has told North Korea that it does not want to see anything happen that could further raise tension, Chinese Foreign Minister Wang Yi said, describing “a serious situation”, after a special envoy from China visited North Korea this week.

The United States has urged China to use its influence to rein in its neighbor.

Speaking to President Park Geun-hye, Chinese President Xi Jinping said he hoped all parties could bear in mind the broader picture of maintaining peace and stability on the peninsula, and “calmly deal with the present situation”, China’s Foreign Ministry said.

“The peninsula cannot be nuclearized, and cannot have war or chaos,” Xi said, also repeating a call for dialogue.

Japan’s Asahi Shimbun newspaper quoted Pentagon officials as saying that fuelling of the rocket appeared to have begun. It cited satellite footage showing increased activity around the missile launch and fuel storage areas, suggesting preparations for a launch could be completed within “a number of days” at the earliest.

A launch would draw fresh U.S. calls for tougher U.N. sanctions that are already under discussion in response to the nuclear test.

What would likely be an indigenous three-stage rocket will be tracked closely. South Korea and Japan have put their militaries on standby to shoot down the rocket, or its parts, if they go off course and threaten to crash on their territory.

“We will, as we always do, watch carefully if there’s a launch, track the launch, (and) have our missile defense assets positioned and ready,” U.S. Defense Secretary Ashton Carter said on Thursday.

“We plan a lot about it. We and our close allies – the Japanese and the South Koreans – are ready for it.”

South Korea has said its Aegis destroyers, its Green Pine anti-ballistic missile radar and early warning and control aircraft Peace Eye are ready.

A U.S. Navy spokesman confirmed the missile tracking ship USNS Howard O. Lorenzen arrived in Japan this week but declined to say if it was in response to the North’s planned launch.

SEARCH FOR CLUES

Boosters and other parts will also be tracked as they splash into the sea, in the hope they can be retrieved and analyzed for clues on Pyongyang’s rocket program.

“Retrieving parts or objects from the launch vehicle are the most important part of the rocket analysis,” said Markus Schiller, a rocketry expert based in Germany.

North Korea said the launch would be during the morning and gave coordinates of where the boosters and payload cover would drop in the Yellow Sea off the Korean Peninsula’s west coast and the Pacific to the east of the Philippines.

The U.S. Navy has sonar equipment and unmanned vehicles that could be used to help recover parts, according to Navy officials. It was not clear if that equipment is in the region.

North Korea last launched a long-range rocket in December 2012, sending what it described as a communications satellite into orbit.

South Korea’s navy retrieved the section of the first stage booster that was part of the fuel tank and one of the four steering engines that confirmed the presence of technology and materials that North Korea had not been known to possess.

Analysis pointed to a launch vehicle capable of carrying a payload of about 500 kg (1,100 lb) more than 10,000 km (6,200 miles), according to South Korea.

A typical nuclear warhead weighs about 300 kg, although North Korea is not believed to have been able to miniaturize a nuclear weapon to that size.

Recovered parts allowed experts to conclude that the second stage booster likely used Soviet-era Scud missile technology and did not use advanced propellant, indicating the rocket was suited for satellite launch but unfit to deliver a warhead.

“My guess is that if you took the rocket they used last time and put a warhead on it you probably would not be able to reach the United States,” said David Wright, co-director and senior scientist at the Global Security Program of the Union of Concerned Scientists.

The search for information on the North’s rocket program will not be easy.

“Some of the more interesting parts, high-efficiency engines and guidance systems, are in the upper stages, and those usually fall far out to sea, at high speed into deep water,” said John Schilling, an aerospace engineer.

“Harder to find than that Malaysian airliner everybody has been looking for all last year.”

(Additional reporting by Andrea Shalal, David Brunnstrom, Ben Blanchard and Elaine Lies; Editing by Tony Munroe, Robert Birsel and Ralph Boulton)

Ex-government employee pleads guilty in nuclear secrets cyber attack scheme

A former government employee who was accused of trying to orchestrate a cyber attack against computers that contained information about nuclear weapons pleaded guilty to a federal computer crime, the Department of Justice announced in a news release on Tuesday afternoon.

Prosecutors said 62-year-old Charles Harvey Eccleston, a former employee of the Nuclear Regulatory Commission, admitted his guilt in the attempted “spear-phishing” attack that took place last January. Eccleston was arrested after an undercover operation in which prosecutors said the accused dealt with FBI employees who had been posing as foreign government officials.

Spear-phishing is a type of cyber attack in which people send authentic-looking emails to their targets, encouraging the recipients to open them. However, the emails contain malicious code.

According to the Department of Justice, Eccleston sent an email that he believed contained a virus to about 80 Department of Energy employees, thinking the code would allow a foreign country to infiltrate or harm their computers. Prosecutors said Eccleston targeted employees “whom he claimed had access to information related to nuclear weapons or nuclear materials.”

The code was harmless and was actually crafted by the FBI, according to the release.

Eccleston, who thought he would be paid roughly $80,000 for sending the spear-phishing email, was arrested last March during a meeting with an undercover FBI employee, prosecutors said.

“Eccleston admitted that he attempted to compromise, exploit and damage U.S. government computer systems that contained sensitive nuclear weapon-related information with the intent of allowing foreign nations to gain access to that information or to damage essential systems,” Assistant Attorney General John P. Carlin said in a statement announcing the guilty plea.

Prosecutors said Eccleston was fired from his job with the Nuclear Regulatory Commission in 2010. He moved to the Philippines the following year and had been living there until his arrest.

The alleged cyber attack wasn’t the first time that law enforcement heard Eccleston’s name.

Prosecutors said the FBI first learned about Eccleston in 2013 after he walked into an embassy in the Philippines and offered to sell a list of 5,000 U.S. government email accounts for $18,800. If the nation wasn’t interested, Eccleston said he would offer the list to China, Iran or Venezuela.

That November, the FBI sent undercover employees to meet with Eccleston and had them pose as foreign government officials. One FBI employee bought a list of 1,200 email addresses for $5,000, prosecutors said, though an investigation found the accounts were publicly available.

Prosecutors said Eccleston communicated with the employees for “several months,” and offered to help design the spear-phishing emails during a meeting with an undercover FBI employee in June 2014. He made the bogus emails look like advertisements for a nuclear energy conference.

Eccleston pleaded guilty to attempted unauthorized access and intentional damage to a protected computer and faces 24 to 30 months in prison and a $95,000 fine when he is sentenced in April, prosecutors announced.

North Korea tells U.N. agencies it plans satellite launch

SEOUL/WASHINGTON (Reuters) – North Korea told U.N. agencies on Tuesday it plans to launch a satellite as early as next week, a move that could advance the country’s long-range missile technology after its fourth nuclear test on Jan. 6.

News of the planned launch between Feb. 8 and Feb. 25 drew fresh U.S. calls for tougher U.N. sanctions already under discussion in response to North Korea’s nuclear test. State Department spokesman John Kirby said the United Nations needed to “send the North Koreans a swift, firm message.”

Pyongyang has said it has a sovereign right to pursue a space program by launching rockets, although the United States and other governments worry that such launches are missile tests in disguise.

“We have received information from DPRK regarding the launch of earth observation satellite ‘Kwangmyongsong’ between 8-25 February,” a spokeswoman for the International Maritime Organization, a U.N. agency, told Reuters by email.

The International Telecommunication Union, another U.N. agency, told Reuters North Korea had informed it on Tuesday of plans to launch a satellite with a functional duration of four years, in a non-geostationary orbit.

It said the information provided by North Korea, whose official name is the Democratic People’s Republic of Korea, was incomplete, and that it was seeking more details.

U.S. officials said last week that North Korea was believed to be making preparations for a test launch of a long-range rocket, after activity at its test site was observed by satellite.

The White House said on Tuesday that any satellite launch by North Korea would be viewed as “another destabilizing provocation.” U.S. Assistant Secretary of State Daniel Russel, the senior U.S. diplomat for East Asia, told reporters it “argues even more strongly” for tougher U.N. sanctions.

Russel said a launch, “using ballistic missile technology,” would be an “egregious violation” of North Korea’s international obligations.

He said it showed the need “to raise the cost to the leaders through the imposition of tough additional sanctions and of course by ensuring the thorough and rigorous enforcement of the existing sanctions.”

Russel said negotiations were “active” at the United Nations and that the United States and North Korea’s main ally China “share the view that there needs to be consequences to North Korea for its defiance and for its threatening behaviors.”

“Our diplomats are in deep discussion in New York about how to tighten sanctions, how to respond to violations,” he said.

Asked about China’s cautious response to U.S. calls for stronger and more effective sanctions on Pyongyang and Beijing’s stress on the need for dialogue, Russel said:

“Yet another violation by the DPRK of the U.N. Security Council resolution, coming on the heels of its nuclear test, would be an unmistakable slap in the face to those who argue that you just need to show patience and dialogue with the North Koreans, but not sanctions.”

White House spokesman Josh Earnest said China had “unique influence over the North Korean regime” and added: “we … certainly are pleased to be able to work cooperatively and effectively with the Chinese to counter this threat.”

Earlier on Tuesday, China’s envoy for the North Korean nuclear issue arrived in the capital Pyongyang, the North’s KCNA news agency reported.

North Korea last launched a long-range rocket in December 2012, sending an object it described as a communications satellite into orbit.

Western and Asian experts have said that launch was part of an effort to build an intercontinental ballistic missile.

North Korea has shown off two versions of a ballistic missile resembling a type that could reach the U.S. West Coast, but there is no evidence the missiles have been tested.

Pyongyang is also seen to be working to miniaturize a nuclear warhead to mount on a missile, but many experts say it is some time away from perfecting such technology.

North Korea said it successfully tested a hydrogen bomb last month but this was met with skepticism by U.S. and South Korean officials and nuclear experts. They said the blast was too small for it to have been a full-fledged hydrogen bomb.

(Additional reporting by Jack Kim in Seoul, Nobuhiro Kubo in Tokyo and David Brunnstrom, Ayesha Rascoe, Mohammad Zargham and Doina Chiacu in Washington; Editing by Mark Heinrich and Grant McCool)

Agency urges nations to ratify bans on nuclear bomb testing

PARIS (Reuters) – North Korea’s recent nuclear test shows a ratification of an international ban on nuclear bomb tests is more urgent than ever, the head of the Vienna-based organization tasked with enforcing the ban said on Monday.

Negotiated in the 1990s, the Comprehensive Nuclear Test Ban Treaty (CTBT) enjoys wide global support but must be ratified by eight more nuclear technology states – among them Israel, Iran, Egypt and the United States – to come into force.

“We must act urgently,” Lassina Zerbo, executive secretary of the Comprehensive Nuclear Test Ban Treaty Organization (CTBTO) told reporters in Paris after meeting with French Foreign Minister Laurent Fabius.

Tension rose in East Asia last month after North Korea’s fourth nuclear test, this time of what it said was a hydrogen bomb.

“The only way to stop that is for the CTBT to come into force,” said the head of the organization, which is independent but linked to the United Nations.

Zerbo said the nuclear deal agreed between Iran and six other nations last year could help speed up the process, which “has been dragging on for 20 years”, and that he hoped to organize a meeting at the ministerial level in Vienna in June.

The CTBTO hopes the eight nations that have not ratified the treaty could agree to a roadmap in June, that would include a moratorium in the Middle East, a discussion with North Korea to “bring it toward a moratorium” and a trust agreement between China and the United States.

Zerbo said a U.S. ratification was a priority for President Barack Obama but that “his hands are tied because he doesn’t have a majority in the Senate.”

(Reporting by Marine Pennetier; Writing by Michel Rose; Editing by Tom Heneghan)

Japan puts military on alert for possible North Korean missile test

TOKYO (Reuters) – Japan has put its military on alert for a possible North Korean ballistic missile launch after indications it is preparing for a test firing, two people with direct knowledge of the order told Reuters on Friday.

“Increased activity at North Korea’s missile site suggests that there may be a launch in the next few weeks,” said one of the sources, both of whom declined to be identified because they are not authorized to talk to the media.

Tension rose in East Asia this month after North Korea’s fourth nuclear test, this time of what it said was a hydrogen bomb.

A missile test coming so soon after the nuclear test would raise concern that North Korea plans to fit nuclear warheads on its missiles, giving it the capability to launch a strike against rival South Korea, Japan and possibly targets as far away as the U.S. West Coast.

Japan’s Minister of Defense Gen Nakatani has ordered Aegis destroyers that operate in the Sea of Japan to be ready to target any North Korean projectiles heading for Japan, the sources said.

A Defense Ministry spokesman declined to say whether PAC-3 batteries and the Aegis destroyers had been deployed to respond to any threat from North Korea.

Nakatani, asked in a press briefing whether Japan would shoot down any North Korean missile, said: “We will take steps to respond, but I will refrain from revealing specific measures given the nature of the situation.”

The advanced Aegis vessels are able to track multiple targets and are armed with SM-3 missiles designed to destroy incoming warheads in space before they re-enter the atmosphere and fall to there targets.

Japan also has Patriot PAC-3 missile batteries around Tokyo and other sites to provide a last line of defense as warheads near the ground.

Rather than a direct attack, however, Japan is more concerned that debris from a missile test could fall on its territory.

(Writing by Tim Kelly; Editing by Robert Birsel)

U.S. says redesigned missile defense interceptor aces test

WASHINGTON (Reuters) – The U.S. Missile Defense Agency on Thursday said it conducted a successful test of the ground-based U.S. missile defense system managed by Boeing Co aimed at demonstrating the effectiveness of a redesigned “kill vehicle” or warhead built by Raytheon Co.

The test purposely did not include an intercept by a ground-based interceptor launched from Vandenberg Air Force Base in California, but was designed to observe the in-flight performance of the redesigned components and collect data on countermeasures carried by the target, according to statements by the agency and the companies involved.

Raytheon’s exoatmospheric kill vehicle, or EKV, is built to destroy incoming ballistic missiles by colliding them while they are still in space, a concept called “hit to kill.”

Thursday’s test was designed to demonstrate the ability of new “divert thrusters” that were developed by Raytheon to maneuver the warhead after a test failure several years ago.

The test, which involved various elements of the U.S. ballistic missile defense system, took place as U.S. officials said North Korea appeared to be preparing for a possible space launch that could advance its development of intercontinental ballistic missiles.

News of the possible North Korean space launch comes weeks after a fourth nuclear test conducted by Pyongyang on Jan. 6 that has raised concerns worldwide.

MDA said program officials would evaluate the performance of the U.S. missile defense system during Thursday’s test using telemetry and other data gathered during the test.

Raytheon’s EKV has an advanced, multi-color sensor used to detect and discriminate incoming warheads from other objects in space. It has its own propulsion, communications link, discrimination algorithms, guidance and control system and computers to support target selection and intercept.

Riki Ellison, founder of the nonprofit Missile Defense Advocacy Alliance, said the test demonstrated new technology developed to make the EKV more reliable, which in turn would allow the U.S. military to shoot fewer interceptors at each incoming missile threat.

He said the successful test would “provide confidence to our public, reliability to the NORTHCOM (U.S. Northern Command) commander and deterrence against North Korea,” he said.

Ellison urged U.S. officials to add 10 more ground-based interceptors to the California site to provide an additional layer of defense for Hawaii and the western United States.

The U.S. military is already adding 14 interceptors to the 30 already in place, but those missiles will go to the other interceptor site in Alaska.

(Editing by Nick Macfie)

‘Doomsday Clock’ countdown still at 3 minutes to midnight, closest since 1984

The countdown to global catastrophe remained at three minutes to midnight, scientists announced Tuesday, warning the planet was still perilously close to experiencing a disaster.

The Bulletin of the Atomic Scientists, which sets the hands of a metaphorical Doomsday Clock, announced the countdown would stay at the position it reached last year. It’s the closest the clock has been to midnight, or a catastrophic event, since the height of the Cold War in 1984.

The nonprofit determines the clock’s position after analyzing threats to human existence, particularly nuclear weapons and climate change. Only once have the hands ever been closer to midnight, a seven-year stretch during the 1950s following the world’s first hydrogen bomb tests.

In a statement, the Bulletin hailed the Iran nuclear deal and Paris Agreement on climate change, both of which were approved last year, as “major diplomatic achievements,” though said they “constitute only small bright spots in a darker world situation full of potential for catastrophe.”

The Bulletin said the Joint Comprehensive Plan of Action, the formal name for the deal that restricts Iran’s ability to develop atomic weapons, was overshadowed by rising tensions between Russia and the United States, both of whom are modernizing their nuclear arsenals, and the fact that China, Pakistan, India and North Korea are working to bolster their atomic capabilities.

The Bulletin called the Paris Agreement, a pledge signed by nearly 200 countries that aims to reduce carbon emissions and keep global temperatures from reaching long-feared levels, another important development. But the scientists noted it’s still not clear exactly how the nations will meet that goal, and the agreement was signed during the hottest year on record.

The scientists also cited ongoing conflicts in the Ukraine and Syria in their statement.

“The world situation remains highly threatening to humanity, and decisive action to reduce the danger posed by nuclear weapons and climate change is urgently required,” the Bulletin said.

The Bulletin was founded in 1945 by scientists who helped builds the world’s first atomic bomb. It established the Doomsday Clock two years later, and decides where to set its hands each year.

The clock can be moved back if the global outlook improves, and moved up if it worsens.

The closest the clock has ever been to midnight was from 1953-59, when the Bulletin said the world was only two minutes from doomsday following the hydrogen bomb tests. Conversely, the clock reached a record 17 minutes to midnight from 1991-94 after the Cold War subsided.

The clock was set at five minutes to midnight in 2012, but the Bulletin adjusted it last year because of climate change and nuclear weapons. In Tuesday’s statement, the Bulletin expressed “dismay” that world leaders had still not taken more aggressive steps to address those issues.

“When we call these dangers existential, that is exactly what we mean: They threaten the very existence of civilization and therefore should be the first order of business for leaders who care about their constituents and their countries,” the Bulletin said in its statement.

The International Campaign to Abolish Nuclear Weapons echoed those calls.

“The Bulletin’s warning should be taken seriously by world leaders,” the campaign’s executive director, Beatrice Fihn, said in a statement.“The risk of use of nuclear weapons is on the rise. If a nuclear weapon was detonated, the effects would be devastating and the international community would be unable to cope with the aftermath. The status quo is no longer an option.”