Volkswacht Bodensee - Hong Kong democracy activist Wong pleads guilty to foreign collusion: AFP

He is accused of asking foreign countries, individuals or institutions to "impose sanctions or blockade, or engage in other hostile activities" against Hong Kong and China in 2020, after Beijing imposed a national security law on the finance hub.

The 29-year-old Wong, one of the most recognisable faces of Hong Kong's now-quashed democracy movement, is already serving a nearly five-year sentence for subversion and was due to be released next year.

Rights groups have said the new charges, which could see Wong sent to prison for life, aim to keep him behind bars as long as possible.

Wong sat in the courtroom dock as the charges were read out, before confirming his guilty plea.

He smiled and nodded in thanks after a supporter in the public gallery shouted "hang in there!".

Prosecutors said Wong and other activists had been lobbying on social media to get attention and support from abroad.

Wong had written for newspapers and spoken to media outlets to call for international sanctions against China and Hong Kong after the security law took effect, and met with foreign politicians including former US House speaker Nancy Pelosi and current Secretary of State Marco Rubio, prosecutors added.

After the charges were read out to him, he stood up and told the judge loudly: "confirm".

Wong was among dozens of pro-democracy campaigners convicted in the city's largest national security trial after their involvement in informal elections in 2020.

The former student leader has been a thorn in Beijing's side for more than a decade after shooting to prominence during the 2014 Umbrella Movement protests.

He was involved in the huge and sometimes violent democracy rallies in 2019 that triggered Beijing's imposition of the national security law on Hong Kong the following year.

N.Schaad--VB