China Targets U.K.’s Hong Kong Passports Over Citizenship Plan

Chinese authorities won’t consider the British National Overseas passport a valid travel document starting Sunday—the day the U.K.’s plan starts—and retains the right to take further measures, Foreign Ministry spokesman Zhao Lijian said Friday, according to state broadcaster China Central Television. Hours earlier, the British government had announced more details of the visa plan, which was made in response to China imposing national security legislation on Hong Kong in June.

The move is more symbolic, with limited impact on holders of BNO passports, because people traveling through Hong Kong and mainland China border checkpoints typically use their Hong Kong identity card and a “return home card” issued by Chinese authorities, respectively. A passport is used only upon entering and exiting other countries.

China and the U.K. have exchanged barbs over China’s handling of Hong Kong, a former British colony that was returned to Beijing in 1997. The U.K. granted the right to a BNO passport for Hong Kong residents born before the handover as part of the sovereignty deal, though it previously conferred no citizenship rights.

Under the U.K.’s new plan, BNO passport holders who apply for a visa can convert to British citizenship after five years of settling in the country. China has expressed anger because offering a path to citizenship wasn’t what was agreed upon before Hong Kong was returned.

“The British side ignored the fact that Hong Kong has been returned to China for 24 years, ignored China’s solemn position and blatantly violated its promises,” Mr. Zhao said. “China is strongly indignant and firmly opposes this.”

There were close to half a million BNO passport holders as of Oct. 2, according to the British Home Office, which didn’t specify how many of those also held alternative travel documents. In the city of 7.5 million, the U.K. estimated, there were 2.9 million BNO citizens eligible to move to the U.K., with an additional 2.3 million eligible dependents.

In an impact assessment published by the Home Office in October, the U.K. estimated that up to 153,700 BNO status holders and their dependents would take up the route in the first year and up to 322,400 over five years. The moves could have a net benefit to the U.K. of the equivalent of $3.29 billion to $3.98 billion over five years, the report said.

“I am immensely proud that we have brought in this new route for Hong Kong BNOs to live, work and make their home in our country,” British Prime Minister Boris Johnson said in the announcement Friday. “In doing so, we have honored our profound ties of history and friendship with the people of Hong Kong, and we have stood up for freedom and autonomy—values both the U.K. and Hong Kong hold dear.”

Write to Natasha Khan at natasha.khan@wsj.com