Britain will on Monday announce plans to suspend or revoke its extradition treaty with Hong Kong, but will stop short of sanctioning Chinese officials, the South China Morning Post has learned.

The move will further exacerbate London’s diplomatic stand-off with Beijing, as US Secretary of State Mike Pompeo begins his London visit to hammer out an Anglo-American strategy on China with Prime Minister Boris Johnson.

Foreign Secretary Dominic Raab is expected to make the announcement on the Hong Kong treaty when he addresses Parliament on Monday, after weeks of lobbying from lawmakers to suspend a legal instrument they fear could be used by Hong Kong for political persecution in future.

The Post was briefed about Raab’s move by a source with knowledge of his thinking after the foreign secretary signalled that an imminent change to the extradition treaty could be under way.

“On Hong Kong, I'm going to go to the House of Commons tomorrow to make a further statement on the work we've been doing with our partners in government," Raab told Sky News.

"I've said that we'd review a whole range of other considerations,” Raab said. "One of the things that we reviewed is our extradition arrangements, and I will be updating the House on the conclusion of that review, along with other things that we've been looking at, tomorrow."

Hong Kong student activist Nathan Law Kwun-chung, who has recently fled to London, said on Twitter, that the move would receive support in Parliament.

“Talked to many members of the parliament on this issue, and got very strong support on the idea of suspending the extradition treaty with Hong Kong,” Law tweeted, adding: “Change is happening.”

Iain Duncan Smith, ex-leader of the Conservative Party and co-founder of the Inter-Parliamentary Alliance on China, said: “If tomorrow the UK Foreign Secretary Dominic Raab decides to suspend the extradition treaty … this is the right thing to do in response to the Chinese government crackdown on people in Hong Kong.”

But sources say Raab is unlikely to sanction any Chinese or Hong Kong officials, a step that China has repeatedly warned Britain not to take.

“If UK government goes that far to impose sanctions on any individual in China, China will certainly make a resolute response to it,” Chinese ambassador to the UK, Liu Xiaoming, told BBC on Sunday.

“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,” Liu added.

China’s imposition of national security laws has been followed by rapidly worsening relations between Beijing and London. The UK has already agreed to let up to 3 million Hongkongers with British National (Overseas) passports to relocate there, with a path to British citizenship, citing Beijing’s violation of the Sino-British Joint Declaration.

The UK will become the latest Five Eyes member to cut off fugitive-transfer arrangements with its former colony in the wake of Beijing’s imposition of the new national security law.

Canada and Australia have suspended their treaties with Hong Kong, citing fear of political persecution. The US was preparing a similar move last week, while New Zealand was reassessing the legal instrument as part of a “deliberate, considered review” of its relations with Hong Kong.

According to the Mutual Legal Assistance in Criminal Matters (United Kingdom) Order, enacted in 2002, either Hong Kong or the UK may terminate the agreement at any time by giving notice to the other.

In that event, the agreement will cease to have effect on receipt of that notice. Requests for help which have been received before termination would still be processed in accordance with the terms of this agreement as if it was still in force.

The UK will also become the first European country to make the move, as the European Union has also been debating whether to nullify the extradition treaties between Hong Kong and Belgium, Czech Republic, Denmark, Finland, France, Germany, Ireland, Italy, the Netherlands, Poland, Portugal, Spain and Sweden.