Police have arrested almost 300 climate change activists in London after two days of protests.
The activists blocked some of London's most important junctions, including Oxford Circus and Marble Arch, causing traffic chaos.
The protests, led by British climate group Extinction Rebellion, brought parts of central London to a standstill again on Tuesday.
Extinction Rebellion, which made headlines with a semi-nude protest in the House of Commons this month, is demanding that the government reduce greenhouse gas emissions to net zero by 2025.
Police said they expected the demonstrations to continue in coming weeks and had to strike a balance between allowing the right to peaceful protest and ensuring disruption was kept to a minimum.
"Ongoing demonstrations are causing serious disruptions to public transport, local businesses and Londoners who wish to go about their daily business," Chf Supt Colin Wingrove said.
Activists had been told they must confine any demonstrations to the Marble Arch area, and police were acting against protesters in other areas.
More than a dozen activists had been arrested at Waterloo Bridge near Parliament by lunchtime on Tuesday.
Others were sitting in the road with linked arms, chanting at the police "Rebellion, rebellion," and "We are peaceful. What about you?"
Five of the arrests were for criminal damage after the Royal Dutch Shell building near the River Thames was hit on Monday.
Two protesters on Monday climbed up scaffolding, writing "Shell Knows!" in red paint on the front of the building and three glued their hands to revolving doors at the entrance.
Tents littered the prime shopping area of Oxford Circus on Tuesday morning, with some activists huddled beneath a model boat with the words "Tell the truth" across its side. One placard read: "Rebel for life".
Activist Katy Fowler, 39, from Machynlleth in Wales, said reaction from the public had been very positive.
"People have come up to us to thank us emphatically," Ms Fowler said. "There is an awareness and a hunger for something to be done."
The Met said 290 people had been arrested by Tuesday evening.
The activists caused 55 bus routes to close, affecting 500,000 people.
Sadiq Khan, the Mayor of London, said he "shared the passion" of the activists but he was "extremely concerned" about plans some protesters had to disrupt the London Underground on Wednesday.
Mr Khan said it was "absolutely crucial" to get more people to use public transport to tackle climate change.
"Targeting public transport in this way would only damage the cause of all of us who want to tackle climate change, as well as risking Londoners' safety, and I'd implore anyone considering doing so to think again," he said.
Extinction Rebellion said it wanted to cause disruption until April 29.
Organisers said protests had been held in more than 80 cities across 33 countries.
