WASHINGTON (AFP) - The United States said on Thursday (June 3) that it stands "with the people of China" in their fight for human rights on the eve of the anniversary of Beijing's Tiananmen crackdown, amid heightened tensions between the two economic giants.

US Secretary of State Antony Blinken said his country will "honour the sacrifices of those killed 32 years ago, and the brave activists who carry on their efforts today in the face of ongoing government repression".

"The United States will continue to stand with the people of China as they demand that their government respect universal human rights," Mr Blinken said, while also calling for "transparency" over Tiananmen Square.

This, he said, included "a full accounting of all those killed, detained or missing".

While discussion of the tanks and troops that quelled peaceful democracy protesters in Beijing on June 4, 1989, are all but forbidden in mainland China, huge candlelight vigils have been held the last three decades in the semi-autonomous Hong Kong.

The city's traditional day of pro-democracy people power, however, has been squashed this year, with thousands of police slated to enforce a ban on protests, and officials warning that a sweeping new national security law could be wielded against those disobeying.

Last year's vigil was also banned on the grounds of the coronavirus, but tens of thousands defied the ban and rallied anyway.

"The Tiananmen demonstrations are echoed in the struggle for democracy and freedom in Hong Kong, where a planned vigil to commemorate the massacre in Tiananmen Square was banned by the local authorities," Mr Blinken said.

The statement came hours after US President Joe Biden expanded a blacklist of Chinese firms that are off-limits to American investors over their links to Beijing's "military-industrial complex".

Washington is reviewing its diplomatic position with China on issues spanning trade, technological supremacy and rights, while it steps up efforts to hook Western democracies into a united diplomatic front against perceived Chinese aggression.