The US, UK, Australia and Canada have issued fresh condemnation of Beijing's new security law for Hong Kong, which they say has "flourished as a bastion of freedom".
They say the international community has a "significant and long-standing stake" in its prosperity and stability.
China's move to impose the new law during a global pandemic risked undermining trust in governments and international co-operation, they said.
China has rejected foreign criticism.
The law – approved by China's parliament on Thursday – has already sparked a new wave of anti-mainland protest in Hong Kong.
On Wednesday, US Secretary of State Mike Pompeo said developments in Hong Kong meant it could no longer be considered to have "a high degree of autonomy" from mainland China.
This could lead to Hong Kong being treated the same as mainland China under US law, which would have major implications for its trade hub status.
The UK on Thursday said visa rights for 300,000 overseas UK citizens in Hong Kong would be extended into a "pathway to future citizenship" if China did not suspend its security law plans.
What is in the new statement?
Direct imposition of the security law by Beijing rather than through Hong Kong's own institutions would "curtail the Hong Kong people's liberties" and "dramatically erode Hong Kong's autonomy and the system that made it so prosperous", the statement says.
It would also conflict with China's international obligations within the Sino-British declaration, under which Hong Kong was returned to China, and would both undermine the "one country, two systems" principle and "raise the prospect of prosecution in Hong Kong for political crimes".
The allies also say they are "deeply concerned" that the new law will deepen divisions in Hong Kong, which has seen repeated waves of protests and clashes over the territory's relationship with the mainland.
"Rebuilding trust across Hong Kong society by allowing the people of Hong Kong to enjoy the rights and freedoms they were promised can be the only way back from the tensions and unrest that the territory has seen over the last year," the statement says.
The US and its allies urge China to work with Hong Kong's government and people to find a "mutually acceptable accommodation".
In other reaction, Japan said Hong Kong was an "extremely important partner" and that democracy and stability there must be maintained.
What is the law about?
China's parliament has backed the security legislation, which would make it a crime to undermine Beijing's authority in Hong Kong.
The resolution – which now passes to China's senior leadership – could also see China installing its own security agencies in the region for the first time.
Full details about exactly what behaviour will be outlawed under the new security law are not yet clear. It is due to be enacted before September.
However it is expected to criminalise:
- secession – breaking away from the country
- subversion – undermining the power or authority of the central government
- terrorism – using violence or intimidation against people
- activities by foreign forces that interfere in Hong Kong
Experts say they fear the law could see people punished for criticising Beijing – as happens in mainland China. For example, Nobel Laureate Liu Xiaobo was jailed for 11 years for subversion after he co-authored a document calling for political reform.
China's foreign ministry in Hong Kong said it "firmly opposed and refuted" Mr Pompeo's assertion that Hong Kong had lost its autonomy and urged the US to "immediately stop meddling" in China's internal affairs.
It described US criticism of the new draft law as "utterly imperious, unreasonable and shameless".
Hong Kong's leader Carrie Lam has denied that the law would curtail the rights of Hong Kongers and said it was a "responsible" move to protect the law-abiding majority.