The US government will begin eliminating special policy exemptions it grants Hong Kong, following its determination earlier this week that the city is "no longer autonomous" from mainland China, President Donald Trump announced on Friday.

The move will affect "the full range of agreements" the US has with Hong Kong, Trump said in the Rose Garden at the White House, including its extradition treaty with the city and economic privileges enshrined in US law that differentiate it from mainland China.

"We will take action to revoke Hong Kong's preferential treatment as a separate customs and travel territory from the rest of China," said Trump, indicating that the State Department's travel advisory for the city would be updated "to reflect the increased danger of surveillance and punishment by the Chinese state security apparatus".

The US would also take steps to sanction Chinese and Hong Kong officials "directly or indirectly involved in eroding Hong Kong's autonomy", he said, echoing the language of legislation enacted in November that requires a punitive response from the executive branch in such circumstances.

The announcement came a week after Beijing declared it planned to institute a new security law tailor-made for Hong Kong that would prohibit acts of subversion, sedition and secession " a move that critics fear will effectively criminalise all forms of dissent and opposition activity.

The new legislative action, which the National People's Congress officially approved on Thursday, would extend the reach of China's "invasive state security apparatus into what was formerly a bastion of liberty", Trump said, accusing Beijing of replacing its "promised formula of 'one country, two systems' with 'one country, one system'".

"This is a tragedy for the people of Hong Kong, the people of China, and indeed the people of the world," he said.

Trump, who had tweeted "CHINA!" earlier in the morning, announced the bombshell move during a Rose Garden briefing at which he read his statement and took no questions from reporters.

The announcement about Hong Kong came with other measures targeting Beijing, including Trump's declaration that the US would withdraw from the World Health Organisation (WHO) over accusations of a China-centric bias.

It is not clear how Trump will achieve that, since much of the financing or WHO is appropriated by Congress and the president ordinarily lacks the authority to redirect congressionally mandated funding.

Trump also said the US would take steps to protect American universities from China-originated attempts to steal US technology. His administration will also suspend the entry of "certain foreign nationals from China" identified as potential security risks, Trump said, without elaborating.

US Secretary of State Mike Pompeo had hinted at imminent punitive measures against Beijing on Thursday, telling Fox that Trump would make announcements addressing "the threat to the United States of America, the American people's security, as it emanates from this tyrannical regime inside of China".

Earlier this week, Beijing vowed to take "necessary countermeasures" against any "erroneous" measures taken by Washington in response to the new legislation, though did not specify how it would retaliate.

The State Department officially declared that Hong Kong was "no longer autonomous" from mainland China on Wednesday, a move that drew sharp criticism from both Beijing and the government in Hong Kong.

Pompeo had "misrepresented" the relationship between the Hong Kong and central governments, "smeared" the implementation of the "one country, two systems" framework and "interfered" in Hong Kong's internal affairs, the city's government said on Thursday.

Under legislation enacted before Hong Kong's handover from British to Chinese rule in 1997, the US maintains a trade and investment relationship with Hong Kong that is distinct from the mainland, shielding the city from the US-China trade war.

In his report to Congress, Pompeo said he could "no longer certify that Hong Kong continues to warrant such treatment," citing the new national security law as well as other recent developments.

Hong Kong had flourished for decades as a "bastion of liberty", Pompeo added, expressing the hope that he could one day recertify the territory as warranting preferential treatment under US law.

"Given present circumstances, the chance of that happening is remote," he wrote. "In the meantime, the United States stands with the people of Hong Kong as they struggle against the CCP's increasing denial of the autonomy they were promised."

This article originally appeared in the South China Morning Post (SCMP), the most authoritative voice reporting on China and Asia for more than a century. For more SCMP stories, please explore the SCMP app or visit the SCMP's Facebook and Twitter pages. Copyright © 2020 South China Morning Post Publishers Ltd. All rights reserved.

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