A new British policy allowing Hong Kong residents to claim British citizenship is a “violation of international law” and interferes with China’s internal affairs, China’s embassy in London said on Thursday, Reuters reports.

Britain’s interior minister Priti Patel said in a written statement on Wednesday that Hong Kong people with British National Overseas visas will be able to apply for citizenship starting from January 2021.

The Chinese embassy said in a statement posted on its website that Beijing would respond strongly, adding that Britain should immediately correct its mistakes.