Protesters hold up placards as they gather in central London to attend a march organised by StandwithHK and D4HK  in support of anti-government protests in Hong Kong. Photo: AFP/Isabel INFANTES

LONDON: Demonstrators backing protesters in Hong Kong marched in London on Saturday, as counter-protesters staged a rival rally.

More than a thousand people took part in the two demonstrations in the British capital.

Protesters supporting the activists paraded banners reading "Will Britain hold China to its promise on Hong Kong's freedom?", "Power to the people: stand with Hong Kong" and "Will Boris surrender to China?", referring to new Prime Minister Boris Johnson.

Others said "The only place I want pepper is in my noodle soup", "SOS: please save Hong Kong" and "No China extradition".

The gathering was organised by the StandwithHK and D4HK groups.

The old British colonial Hong Kong flag was seen at the demonstration.

Britain handed control of Hong Kong back to China in 1997 on the basis of the Joint Declaration it signed with Beijing, which guarantees freedoms in the semi-autonomous city until 2047.

Counter-protesters waved Chinese flags and held up signs saying "traitor", "one nation, one China" and "Hong Kong is part of China forever".

Meanwhile in Paris, during the weekly "yellow vest" demonstrations, some participants also showed their support for the Hong Kong protesters.

In Hong Kong, protesters kicked off a weekend of fresh rallies on Saturday in a major test for the movement following criticism over an airport protest earlier this week -- and as concerns mount over Beijing's next move.

Ten weeks of demonstrations have plunged the international finance hub into crisis, with communist-ruled mainland China taking an increasingly hardline tone.