WASHINGTON (BLOOMBERG) - The US is imposing sanctions on four more people in its continuing response to China's crackdown on dissent in Hong Kong, the Treasury Department announced Monday (Nov 9).

Earlier, the US suspended its extradition treaty with Hong Kong, ended reciprocal tax treatment on shipping with the former British colony, and sanctioned senior officials who oversee Hong Kong, including the city's leader, Carrie Lam.

The Treasury Department added four Chinese individuals to its specially designated nationals list without further description. An agency spokesman didn't reply immediately to a request for comment.

The moves are part of the administration's efforts to pressure China over the imposition of a national security law that has led to charges against pro-democracy activists, according to people familiar with the matter.

They follow up on an executive order to end preferential trading treatment for the city, which President Donald Trump and his team say is being treated as just another Chinese city.

President-elect Joe Biden has also been strongly critical of China over human rights issues including its crackdown in Hong Kong.

In response to earlier moves, China urged the US to cease its "wrong moves" toward Hong Kong, with Foreign Ministry spokesman Zhao Lijian reaffirming Beijing's position that the city's affairs were a domestic matter.

Hong Kong's government said it "strongly objects" and "deplores" the Trump administration's decision, repeating its vow to take up the complaints at the World Trade Organisation.

China responded with retaliatory measures against US senators and human rights activists, although Beijing has so far avoided senior White House officials.