The United States on Friday imposed sanctions on Hong Kong Special Administrative Region (HKSAR) Chief Executive Carrie Lam and other officials, according to the U.S. Treasury Department's website.

It came after U.S. President Donald Trump signed the Hong Kong Autonomy Act last month to allow the U.S. to impose sanctions and visa restrictions on Chinese officials and financial institutions involved in the imposition of the national security law for the HKSAR.

China has expressed firm opposition against the U.S. decision to impose visa restrictions on Chinese officials over Hong Kong related issues.

A spokesperson for the Chinese Embassy in the U.S. said that the national security legislation for the HKSAR, which the U.S. has cited as one of the reasons for the act, targets a very narrow category of acts that seriously jeopardize national security and will improve Hong Kong's legal system, bring more stability to Hong Kong, and contribute to the practice of "One Country, Two Systems" and Hong Kong's long-term prosperity and stability.

The spokesperson pointed out that the legal basis for the Chinese government to govern Hong Kong is China's Constitution and the Basic Law of the HKSAR, not the Sino-British Joint Declaration, adding that as China resumed the exercise of sovereignty over Hong Kong in 1997, all rights and obligations of the British side as prescribed in the Joint Declaration were completed.

No one has any legal grounds or right to make irresponsible comments on Hong Kong affairs citing the Sino-British Joint Declaration, the spokesperson said.

The HKSAR government also expressed strong opposition, urging the U.S. side to immediately stop interfering in Hong Kong affairs and said the act and the so-called "sanctions" are totally unacceptable and will only harm the relations and common interests between Hong Kong and the United States.

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