Thousands of Extinction Rebellion activists gathered across London in defiance of a police order banning the group’s climate protests in the capital.

Activists also launched legal action against the city’s Metropolitan Police after the force announced the ban.

Calling the Met’s actions “disproportionate and unlawful”, human rights lawyer Tobias Garnett, representing the group, said it would be filing a High Court claim against the order.

He said Extinction Rebellion, which hopes to use direct action to bring greater attention to the worsening climate crisis, was planning to file a claim on Tuesday afternoon and was seeking an expedited hearing.

The group appeared undeterred by the police order which declares any assembly – classed as a gathering of two or more people – linked to the Extinction Rebellion “Autumn Uprising” in London is unlawful.

Extinction Rebellion protesters shut down London roads Show all 59 1 /59 Extinction Rebellion protesters shut down London roads Extinction Rebellion protesters shut down London roads London, UK Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Trafalgar Square Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion protests in Trafalgar Square - 10 October 2019 Angela Christofilou Angela Christofilou/The Independent Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou Extinction Rebellion protesters shut down London roads Extinction Rebellion London march - 12 ctober 2019 Angela Christofilou Angela Christofilou

XR said it intended to target the London Underground later this week.

“We rebel to drive the urgent changes needed to prevent mass extinction and suffering,” it wrote on Twitter.

London’s Mayor Sadiq Khan – who oversees the Metropolitan Police - said he had asked officers to find a way for those who wanted to protest to be able to do so legally and peacefully.

He said he had “received assurances that Extinction Rebellion are not banned from protesting in our city”, adding: “Neither I nor the deputy mayor for policing and crime was informed before the Metropolitan Police took the operational decision to impose a Section 14 order on Extinction Rebellion Autumn Uprising last night. I’ve met with senior officers today to seek further information on why they deemed this necessary.”

A protester scales the walls of parliament (Getty)

Activists nonetheless continued protests in the capital in defiance of the order, targeting the Department for Transport. Gail Bradbrook, the group’s founder, climbed the entrance while other demonstrators glued themselves to the building.

Others were also arrested after blocking the road outside MI5’s headquarters, while others locked themselves to a caravan parked outside Millbank tower.

Police officers spent two hours trying to release their arms and eventually did so by using a magnetic drill.

Parliament Square was also briefly closed after one protester scaled a pillar on the fence that surrounds the houses of parliament. They were later removed and detained.

Ilya Fisher, a fine art photographer from Cornwall, said she was taking part despite never having been arrested before.

“I’m doing this because I want other people to say, ‘Why is such a boring ordinary person doing this?’ and they will look into the climate science,” she said. “The government isn’t protecting us. If we wait until 2050 for the carbon emissions to be reduced it’s way too late.”

Extinction Rebellion has attracted the support of thousands of young people across the world.

Extinction Rebellion’s grandparents group gathers opposite Buckingham Palace (AFP)

But opposite Buckingham Palace, a group of grandparents and older activists gathered and launched into song.

“This nanna is revolting,” one demonstrator’s sign read.

Defending the order, Laurence Taylor, the Metropolitan Police’s deputy assistant commissioner, said: “This was an operational policing decision to help us get London moving again. After nine days of disruption, we felt it is entirely proportionate and reasonable to impose this condition because of the cumulative impact of these protests.

Support free-thinking journalism and attend Independent events

“A significant policing operation continues and we will take robust action against anyone engaged in unlawful protests at locations targeted by Extinction Rebellion.”

The force said 1,489 people had so far been arrested in connection with the wave of activism.

Ninety-two people have been charged with a range of offences, including failing to comply with the Section 14 order, criminal damage and obstruction of a highway.