Britain will on Monday suspend its extradition treaty with Hong Kong in a further escalation of its dispute with China over its introduction of a national security law for the former British colony, newspapers reported.
Foreign Secretary Dominic Raab, who on Sunday accused China of "gross" human rights violations, will announce the suspension of the treaty in parliament, the Times and Daily Telegraph newspapers said, citing sources.
Britain's Foreign Office declined to comment.
Education Minister Gavin Williamson declined to comment on the reports ahead of Raab's statement, which is expected at around 1430 GMT, but he said Britain was always ready to speak out when it disagreed with Beijing.
"We want to work with China and we always will want to work with China - it's an important player on the world stage. But we must always, and will always, speak out where we think they're doing things that are wrong," he told Sky News.
Any move on extradition would be another nail in the coffin of what former Prime Minister David Cameron has cast as a "golden era" of ties with Communist Party rulers in the world's second-largest economy.
But London has been dismayed by a crackdown in Hong Kong, which returned to Chinese rule in 1997, and the perception that China did not tell the whole truth over the coronavirus outbreak.
Last week Prime Minister Boris Johnson ordered Huawei Technologies equipment to be purged completely from Britain's 5G network by the end of 2027.
China has accused Britain of pandering to the United States.
Britain says the new national security law breaches the guarantees of freedoms, including an independent judiciary, that have helped keep Hong Kong one of the world's biggest and most freewheeling financial hubs since 1997.
Hong Kong and Beijing officials have said the law is vital to plug holes in national security defences exposed by recent pro-democracy and anti-China protests. China has repeatedly told Western powers to stop meddling in Hong Kong's affairs.
Earlier on Sunday, China's ambassador to Britain warned of a tough response if London attempted to sanction any of its officials, as some lawmakers in Johnson's Conservative Party have demanded.
"If UK government goes that far to impose sanctions on any individual in China, China will certainly make a resolute response to it," Liu Xiaoming told the BBC's Andrew Marr Show.
"You've seen what happens in the United States - they sanction Chinese officials, we sanction their senators, their officials. I do not want to see this tit-for-tat happen in... China-UK relations."
Raab told the same programme he would not be drawn on future additions to Britain's sanctions list but he denied that Britain would be too weak to challenge China through this channel.