LONDON: Thousands of climate change demonstrators thronged central London on Monday, as environmental activist group Extinction Rebellion held its latest round of protests, promising two weeks of disruption.

Protesters were greeted with a visibly heavy police presence as they converged on Trafalgar Square in the heart of the British capital, where they rallied with a marching band and speeches.

The latest action - branded the "Impossible Rebellion" - saw participants block roads leading to the square, deploying a large pink structure with the slogan "come to the table" written on it.

"What are you waiting for? Your local area to flood, or your street to get blocked with rubble and cars?" Extinction Rebellion's UK branch said on Twitter.

"The #ClimateEmergency is happening now, and the rebellion for life is happening now."

The group, formed in Britain in 2018, is a network of climate activists who use civil disobedience to spotlight inaction on global warming.