China on Tuesday warned of "consequences" after Britain suspended its extradition treaty with Hong Kong in protest at a controversial new security law in the territory.

London's decision threatened to put Sino-British ties under further strain, days after the UK vowed to remove all Huawei 5G equipment from its networks, and as British politicians criticise China for its treatment of ethnic minority groups.

A statement on the website of the Chinese Embassy in Britain criticised the suspension of the treaty and said "the UK side has gone even further down the wrong road".

"China urges the UK side to immediately stop interfering in Hong Kong affairs, which are China's internal affairs," the statement said.

"The UK will bear the consequences if it insists on going down the wrong road."

Britain's extradition treaty suspension comes after similar tough action against China by the United States, Canada and Australia.

Foreign Secretary Dominic Raab confirmed the widely expected move in parliament on Monday, despite repeated Chinese warnings that Britain was making a grave foreign policy error and risked reprisals.

"The government has decided to suspend the extradition treaty immediately and indefinitely," he said, adding that the security law -- which allows some cases to be tried in mainland China -- undermines key British assumptions about the extradition treaty. 

Critics have said the security law is an erosion of civil liberties and human rights in the semi-autonomous financial hub.

Britain this month offered what amounted to a pathway to citizenship to up to three million Hong Kong residents in response to the controversial law.