Beijing has imposed sanctions on several former Trump administration officials, including ex-US secretary of state Mike Pompeo, accusing them of having "seriously violated" China's sovereignty.
China announced the decision a day after Donald Trump's administration declared that the repression and detention of more than a million Muslim Uighurs in the northwestern Xinjiang region amounted to genocide.
The Chinese foreign ministry said it was targeting 28 individuals, including Matthew Pottinger, the former deputy national security adviser who was one of the main drivers of Washington's hawkish stance towards China.
The list also included Robert O'Brien, Mr Trump's national security adviser, and John Bolton, one of his predecessors in the position.
“Over the past few years, some anti-China politicians in the US ... have executed a series of crazy moves which have gravely interfered in China’s internal affairs,” the foreign ministry said.
The former officials on the list and their families would be barred from entering mainland China, Hong Kong and Macau, it said, and companies and institutions associated with the 28 targets would be restricted from conducting business with China.
The Chinese foreign ministry revealed the names of 10 of the targeted Americans. The Chinese embassy in Washington did not respond to a request for clarification.
The move marks the latest deterioration in relations between Washington and Beijing, which have reached their lowest point since diplomatic ties were established more than three decades ago.
"It's primarily a signal meant for the outgoing Trump administration, and a settling of accounts. But at the same time, it's a warning for future US politicians," said Wu Xinbo, dean of the Institute of International Studies at Fudan University and a government adviser. "Broadcasting their names is a form of insult and humiliation."
New tsar
Mr Biden has vowed to take a tough stance against China, and last year described Chinese president Xi Jinping as a "thug". He recently appointed Kurt Campbell, a veteran Asia expert, to serve as a new tsar for the region, in a move that underscored the administration's focus on China.
Antony Blinken, Mr Biden's nominee for secretary of state, said this week that he disagreed with how Mr Trump had implemented his China policy, but thought the former president "was right in taking a tougher approach".
Avril Haines, who is set to be Mr Biden's director of national intelligence, said she supported "an aggressive stance" towards Beijing. "Our approach to China has to evolve and essentially meet the reality of the particularly assertive and aggressive China that we see today," she said.
Hua Chunying, a foreign ministry spokeswoman, said on Thursday: “We hope the new administration will view China-US relations on a rational basis.”
Few experts believe Mr Biden will be as antagonistic as the Trump administration.
Bonnie Glaser, a China expert at the Center for Strategic and International Studies think-tank, said it appeared to be the first time China had imposed sanctions on US officials. She said it was unclear how strongly Beijing would enforce the measures, since it had only recently begun using sanctions.
Ms Glaser added, however, that the move could make it more difficult for some former officials to get certain jobs in the future. “Company boards and advisory groups may be reluctant to hire individuals on the list to avoid negative impact on their business,” she said.
Ryan Hass, a China expert at the Brookings Institution think-tank, said the Chinese decision was also likely a response to recent efforts by Mr Trump to target Chinese and Hong Kong officials over Beijing's crackdown on the pro-democracy movement in the territory.
Account locked
The warning to companies was designed to “deprive outgoing officials of earning opportunities and to try to deter future officials from advocating policies that could undermine their post-government employment options”.
China's sanctions list also included Peter Navarro, a China hawk who served as a White House trade official, and Steve Bannon, another outspoken critic who served as Mr Trump's presidential campaign manager and White House strategist.
Separately, Twitter said it had locked the account of the Chinese embassy in Washington from posting new tweets after the account this month referred to Uighur women in Xinjiang as “baby-making machines”. Female detainees in Xinjiang’s mass camps have alleged being subjected to forced sterilisations.
The company said the account would remain frozen until the tweet, which violated Twitter’s policy that “prohibits the dehumanisation of a group of people based on their religion ... or ethnicity”, was deleted by the account owner.
Twitter's decision was first reported by Bloomberg. – Copyright The Financial Times Limited 2021