Celebrities including actress Emma Thompson, musician Peter Gabriel and designer and activist Vivienne Westwood joined an estimated 40,000 people to march through Westminster calling on politicians to tackle global warming.
The march and rally was one of 2,000 events taking place in 150 countries around the world ahead of a UN climate summit this week, which more than 120 leaders including David Cameron and US president Barack Obama are expected to attend.
Upwards of 100,000 people are expected to take to the streets of New York, where the summit is being held, for a People’s Climate March.
The UN summit has been convened by secretary-general Ban Ki-moon in a bid to drive action and momentum towards talks in Paris in 2015, where it is hoped a new global climate treaty can be agreed.
In London, campaigners carrying banners that said “renewables rock” and “for the love of polar bears and rhinos” marched through the streets chanting and demanding cleaner energy.
Puppet giraffes, birds and zebras were joined by protesters dressed as pandas and parents with their children in push-chairs. Nathan Williams, a TV director from Kilburn, north-west London, carried his six-year-old daughter, who was dressed as the princess from the film Frozen and held a banner which said: “Keep things frozen.”
He said of climate change: “It’s such a big issue for our lives, and even more for her life.”
Speaking at the start of the march, Thompson said: “This is important for every single person on the planet, which is why it has to be the greatest grassroots movement of all time.”
She said that fossil fuels had been a good idea at the time, like tobacco, but now it was clear they were killing people.
“Climate change has been a bit like everybody playing a deadly game of grandmother’s footsteps for the last 20 years,” she added. “Now this climate change grandmother has turned around and started running towards us. It’s touch and go whether we’re going to survive what we’ve done.”
Thompson has just returned from a trip to the Arctic where, she said, “the effects of the melting ice are written so clearly on the landscape”. She added that everyone had to act on cutting emissions.
“An international climate deal is of absolutely vital importance,” she said. “It must be put into law. It can’t be a non-binding agreement. Those agreements have fallen to pulp in our hands over the last 20 years.”
She criticised Mr Cameron for encouraging oil, gas and coal, and said the politics of fighting climate change were “profound, and deep and dirty”, adding: “This is the battle of our lives. We’re fighting for our children.”
Meanwhile, scientists yesterday warned that global emissions of carbon dioxide are set to rise again this year and will reach a new record high.