In a move seen by some envoys as a diplomatic affront, the government informed about a dozen foreign consulates in a letter that it no longer considered the British National Overseas (BNO) passport a valid travel document as of Jan. 31.

The letter, seen by Reuters, demanded that its Hong Kong passport should be used instead.

A diplomatic row broke out over the BNO in January after Britain introduced a new visa scheme offering a pathway to full citizenship for Hongkongers who want to leave the Chinese-ruled territory.

Britain launched the scheme after Hong Kong passed a sweeping national security law last year, that critics say is crushing dissent in the former British colony.

Almost 3 million Hong Kong residents hold or are eligible for the BNO document, that was created ahead of Britain handing the city back to Chinese rule in 1997.

Hong Kong also started to mirror mainland China by not recognising dual nationality, preventing for the first time foreign diplomats from visiting locals with foreign passports in detention.

“Most countries are going to ignore this,” said one senior Western diplomat who had seen the letter.

“It is the Hong Kong government just trying it on...they have no right to tell any state what foreign passports it can recognise.”

Another envoy described the move as “bordering on belligerent” and said it was not the way the Hong Kong government, generally mindful of the city’s standing as an international financial hub, has traditionally behaved.

The Hong Kong government has yet to respond to Reuters’ request for comment.

A Hong Kong government website lists 14 countries under the reciprocal Working Holiday Scheme, including Japan, Canada, Germany, Britain and Australia.

Officials in Japan, South Korea, Italy and New Zealand confirmed to Reuters that they still recognised the BNO passport for visas. South Korea’s Foreign Ministry added that it had not received the letter while Hungary said it had, and had started talks to change the working holiday programme.

Other nations, including the United States, Finland and Norway, also offer similar arrangements or student exchanges for Hongkongers, and have accepted BNOs from applicants.

It is not known if the United States also received the letter but a State Department spokesman told Reuters the BNO remained valid for visa-issuing purposes and travel to the United States.

Hong Kong’s moves against the BNO followed an announcement from the UK government that its new visa could attract more than 300,000 people and their dependents.

London said it was fulfilling a historic and moral commitment to Hong Kong’s people in the wake of the national security law, which allows for suspects in serious cases to be taken across the border and tried in mainland Chinese courts.

Beijing and Hong Kong authorities say the legislation is necessary to bring stability to the city after anti-government protests flared in 2019.

The UK scheme allows those with BNO status to live, study and work in Britain for five years and eventually apply for citizenship.

Beijing said it would make them second-class citizens, a line propagated by pro-Beijing media commentators in Hong Kong.

Britain handed its former colony back to Chinese rule in 1997 with guarantees its core freedoms, extensive autonomy and capitalist way of life would be protected.

- Additional reporting by Krisztina Than in Hungary, Antoni Slodkowski in Tokyo, Hyonhee Shin in South Korea, Praveen Menon in New Zealand and Crispian Balmer in Italy.