In a statement following the news outlet's closure earlier on Thursday, Biden called on China to stop targeting the independent press and release detained journalists and media executives.

"People in Hong Kong have the right to freedom of the press. Instead, Beijing is denying basic liberties and assaulting Hong Kong's autonomy and democratic institutions and processes, inconsistent with its international obligations," he said.

Apple Daily, Hong Kong's most vocal pro-democracy newspaper, was forced to end a 26-year run amid a national security crackdown that froze the company's funds.

Its closure prompted snaking queues of hundreds of loyal readers at news stands across the city.

"It is a sad day for media freedom in Hong Kong and around the world," Biden said, adding that the publication had been "a much-needed bastion of independent journalism in Hong Kong".

"Through arrests, threats and forcing through a National Security Law that penalises free speech, Beijing has insisted on wielding its power to suppress independent media and silence dissenting views," he said.

Biden vowed that the United States "will not waver in our support of people in Hong Kong and all those who stand up for the basic freedoms all people deserve."

Australian Associated Press