Two British MPs have called on the UK to directly condemn Beijing for failing to hold up its end of the Sino-British Joint Declaration, asking Boris Johnson's government to consider sanctions against Chinese officials and companies.

Thousands, dressed in black, gathered in a public square Friday evening in Hong Kong’s business district in defiance of showers that had swept through the city.

“What is happening in Hong Kong is truly a human rights crisis in the making,” said MP Heidi Allen, in a message read to the crowd. “We mustn’t allow China to use this as an opportunity to bully us into submission, and relinquish our responsibilities.”

“This slow erosion of your freedoms is precisely what the Sino-British Joint Declaration was supposed to avoid when Britain signed that agreement in 1984,” said Tom Watson in a recorded address.

The extradition proposal “clearly breaches that understanding and starts to align Hong Kong’s legal system with that of China; this is not acceptable," he added.