The U.S. House of Representatives passed a bill which will assess annually whether Hong Kong is sufficiently autonomous from mainland China to justify the Asian financial hub's special status with the U.S.
The Hong Kong Human Rights and Democracy Act, which will need to be passed by the Senate before President Donald Trump decides whether to sign it into law, has drawn firm opposition and warnings of retaliatory measures from Beijing.
If passed into law, the bill will direct the U.S. Commerce Department to annually inform Congress on China's alleged "efforts to use Hong Kong to evade U.S. export controls and sanctions." It will also allow the U.S. to impose sanctions on individuals "responsible for abducting and torturing people for exercising internationally recognized human rights" in Hong Kong.
The House passed another bill restricting the export of crowd control technology, such as teargas, and certain crime control and detection technology and software to law enforcement authorities in Hong Kong. It also passed a resolution "condemning" Beijing's interference in Hong Kong and supporting the rights of citizens in the territory to protest.
While Hong Kong is part of China, Washington treats the city as a non-sovereign entity distinct from the mainland in trade and economic matters.
China's Foreign Ministry spokesperson Geng Shuang said: "If the relevant act were to become law, it would not only harm China's interests and China-U.S. relations, but would also seriously damage U.S. interests."
"China will definitely take strong countermeasures in response to the wrong decisions by the U.S. side to defend its sovereignty, security and development interests," Geng said.
The U.S. and China are due to hold a new round of principal-level talks next week in a bid to finalize "phase-one" of their trade deal in November.