Climate activists blocked streets in central London on Monday, kicking off two weeks of planned protest against inaction over climate change.
The Extinction Rebellion activists marched through the capital waving banners and banging drums.
Several of them were arrested including two men who chained themselves to a van.
Monday's protest centered on a giant pink table erected in Leicester square, with the slogan "come to the table" directed at the government.
"I am doing this because I care about the climate emergency. I care about all living things on this Earth and I am doing something about it."
Earlier, the activists gathered in Trafalgar square to listen to speeches before starting their march.
"I'm here fighting for my grandson and my stepson, and his lovely wife, and for generations to come, because this is not going to be nice."
"They're just not listening. They're only interested in economic growth and just look at the weather. You know, economic growth is what causes a broken weather system."
There were also protests on Monday in Oslo, where scores of Extinction Rebellion activists blocked access to Norway's oil and energy ministry for more than five hours.
Extinction Rebellion is planning a series of protests over the next fortnight including several targeting London's financial district, which they blame for helping to fuel climate change.
The group wants an emergency response from governments around the world, as well as a mass move away from polluting industries to avert the worst scenarios of devastation outlined by scientists.