WASHINGTON (Reuters) – The United States on Wednesday issued an advisory warning U.S. companies about the risks they face from maintaining supply chains associated with human rights abuses in China’s western Xinjiang province.

The advisory, issued by the U.S. State, Treasury, Commerce and Homeland Security departments, seeks to add more U.S. pressure on China at a time of heightened tensions over China’s treatment of Muslim Uighurs in Xinjiang and Beijing’s new national security law for Hong Kong.

The advisory said that companies doing business in Xinjiang or with entities using Xinjiang labor face “reputational, economic, and legal risks” from human rights abuses, including forced labor, mass detention and forced sterilization.

“CEOs should read this notice closely and be aware of the reputational, economic and legal risks of supporting such assaults on human dignity,” U.S. Secretary of State Mike Pompeo told reporters on Wednesday.

The action follows a U.S. Commerce Department move last month that added seven companies and two institutions to an economic blacklist for being “complicit in human rights violations and abuses committed in China’s campaign of repression, mass arbitrary detention, forced labor and high-technology surveillance against Uighurs” and others.

China’s foreign ministry said in May it deplored and firmly opposed U.S. sanctions over Xinjiang, calling it a purely internal affair for China.

(Reporting by David Lawder and Daphne Psaledakis; Editing by Chizu Nomiyama and Richard Chang)