BRUSSELS (Reuters) – The European Union is investigating a cyber hack of its diplomatic communications, allegedly by Chinese hackers, that revealed EU concern about U.S. Donald Trump, Russia and Iran, the bloc said on Wednesday.

“The Council Secretariat is aware of allegations regarding a potential leak of sensitive information and is actively investigating the issue,” the body that represents EU governments in Brussels said in a statement.

The Secretariat declined to comment further but said it “takes the security of its facilities, including its IT systems, extremely seriously”, referring to concerns about vulnerabilities in its data systems across 28 EU states.

The New York Times reported late on Tuesday that hackers had broken into the EU’s diplomatic communications for years, downloading cables that showed worries about the Trump administration, struggles to deal with Russia and China, and the threat of Iran reviving its nuclear programme.

More than 1,100 cables were supplied to the Times by security firm Area 1 after it discovered the breach, the newspaper said, adding that Area 1 investigators believed the hackers worked for China’s People’s Liberation Army.

The cables include memorandums of conversations with leaders in Saudi Arabia, Israel and other countries that were shared across the European Union, according to the report.

One cable, the Times said, showed European diplomats describing a meeting between U.S. President Donald Trump and Russian counterpart Vladimir Putin in Finland as “successful (at least for Putin)”.

Another, written after a July 16 meeting, relayed a detailed report and analysis of talks between European officials and Chinese President Xi Jinping, who was quoted comparing Trump’s “bullying” of Beijing to a “no-rules freestyle boxing match”.

A third, from March 7, shows Caroline Vicini, the deputy head of the EU mission in Washington, recommending that the trade bloc’s diplomats describe the United States as “our most important partner”, even as it challenged Trump “in areas where we disagreed with the U.S. (e.g., on climate, trade, Iran nuclear deal)”.

The hackers also infiltrated the networks of the United Nations, the American Federation of Labor and Congress of Industrial Organizations (AFL-CIO), and ministries of foreign affairs and finance worldwide, the Times report added.

(Reporting by Rama Venkat in Bengaluru and Robin Emmott in Brussels; editing by Andrew Roche)