China threatened unspecified "strong countermeasures" if the United States Congress enacts legislation supporting Hong Kong protesters, in a sign of the deepening strain between the world's two largest economies as they attempt to seal a trade deal.
China's Foreign Ministry issued the warning yesterday after the House of Representatives passed a package of measures backing a pro-democracy movement that has rocked Hong Kong for more than four months.
Calling the Bill's passage "extreme hypocrisy" exposing US intent to undermine the city's prosperity, Foreign Ministry spokesman Geng Shuang said in a statement that Beijing resolutely opposed the new measures, and urged US lawmakers to stop interfering in China's internal affairs.
At a regular briefing in the afternoon, Mr Geng reiterated that China's relationship with the US will be damaged and Beijing will take "effective measures" should the legislation become law, without elaborating further.
As a sign of the whipsaw nature of US-China relations, Mr Geng's remarks came one day after he told reporters the two sides were "in unanimous agreement" on the phased trade agreement reached last week.
The Hong Kong Human Rights and Democracy Act was one of four measures passed by the House on Tuesday in unanimous voice votes.
The Bill would require an annual review of whether the city is sufficiently autonomous from Beijing to justify its special trading status with the US.
But it still needs to be passed by the Senate and signed by President Donald Trump before it becomes law. The legislation has bipartisan support in both chambers.
The Hong Kong government expressed regret over the US congressional actions, and a spokesman said foreign legislatures should not interfere in the autonomous region's affairs.
China's representative Liaison Office in Hong Kong and its Hong Kong and Macau Affairs Office (HKMAO) accused the US of gross interference in China's affairs, and said that Washington was "openly blessing the radicals and extremists" in Hong Kong.
HKMAO spokesman Yang Guang said that some protesters had in recent weeks "seriously infringed upon the basic human rights and personal safety" of police officers and the public through the use of violence, including petrol bombs and a homemade remote-controlled explosive device.
The National People's Congress added that the actions of violent protesters had "characteristics of terrorism", and that by passing the Bill, the US House had ignored actions that destabilised Hong Kong in the name of human rights and democracy.
It urged the US Congress to "immediately stop promoting Hong Kong-related Bills and do more things conducive to (the) interests of China and the US".
State-run Xinhua news agency said US and Western intervention in the Hong Kong protests had resulted in a local version of a "colour revolution", and specifically called out US politicians such as Vice-President Mike Pence, Secretary of State Mike Pompeo and Senator Ted Cruz for "fuelling the chaos" through various actions, such as meeting protest leaders.
Other measures passed by the House include a Bill that would halt the export to Hong Kong of crowd-control devices such as tear gas and rubber bullets, while a resolution was adopted that commended the Canadian government for starting extradition proceedings in the US case against Huawei executive Meng Wanzhou.
"This series of hegemonic, despicable and hideous acts has made the world more aware of anti-China forces'... political plot to disrupt Hong Kong and contain China," Xinhua said in one of a number of commentaries.