Britain is considering whether to review a deal allowing its judges to sit on Hong Kong's highest court over concerns China is trampling on the semi-autonomous city's freedoms, its foreign minister said.
A sweeping national security law and the purge of pro-democracy lawmakers had raised "serious" questions over China's pre-handover promise to let the financial hub maintain certain freedoms and autonomy until 2047, Dominic Raab said Monday.
"This has been, and continues to be, the most concerning period in Hong Kong's post-handover history," Raab said in the UK parliament's latest six-monthly report on the former British colony.
He added he had begun consultations "concerning when to review whether it continues to be appropriate for British judges to sit as non-permanent judges on the Hong Kong Court of Final Appeal".
Under a "One Country. Two Systems" deal Hong Kong maintained its independent, common law judiciary -- viewed as one of the bedrocks of the financial hub's identity and economic success.
It is a key factor differentiating the city from mainland China where the opaque legal system is controlled by the Communist Party.
Under the Basic Law -- Hong Kong's mini-constitution -- senior judges from common law jurisdictions are able to sit as non-permanent members of the city's Court of Final Appeal.
If Britain were to pull its judges, it may add pressure to allies like Australia and Canada to do the same.
Western countries say Beijing has prematurely shredded its pre-handover promises with its clampdown, including a broadly worded national security law that was imposed directly on the city in June.
London has angered Beijing by offering Hong Kongers holding British National Overseas passports a route to UK citizenship by relaxing entry and residency requirements.
It has also suspended its extradition treaty with Hong Kong, one of a number of countries to do so.
China says the security law and prosecution of critics is needed to restore stability after last year's huge and often violent protests.
In a response to the latest parliamentary report, China's foreign ministry office in the city said Britain should "wake up from colonial nostalgia and stop interfering in Hong Kong affairs".
Hong Kong's government dismissed the report as "sweeping attacks and groundless accusations."