Environmental campaign group Extinction Rebellion are expecting 50,000 people to descend on Westminster in London over four days of protest it has branded "The Big One."

Some 200 groups, including Greenpeace and Friends of the Earth, are joining forces. Extinction Rebellion has groups across Europe and have a large following in Germany. 

Groups of demonstrators have gathered on the UK capital's streets, chanting, dancing and even lying down outside government departments as they demand urgent action to tackle the climate crisis.

It is the group's first major action since announcing it would move away from more controversial methods of protest and "prioritise attendance over arrest and relationships over roadblocks."

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WHAT IS HAPPENING IN LONDON?

On Saturday, thousands gathered across London, many in costume, with music, including from the Church Of Stop Shopping Choir and special speakers. There was also a biodiversity march and mass 'die-in.'

On Sunday, a 'Running Out Of Time' theme saw protesters intersect with the London Marathon, although organizers from both camps made an agreement not to interrupt the race. 

The fourth and final day on Monday will involve a march 'to end fossil fuels' and a picket line at the Houses of Parliament.

WHAT DO CAMPAIGNERS WANT?

Extinction Rebellion (XR) said the groups had issued the British government with a demand to end all licences, funding and approval for new fossil fuel projects and to immediately create "emergency citizen assemblies."

If the government failed to agree to discuss these by a deadline of 1600 GMT on Monday April 24, XR said it would increase its activities.

"This time we won't be alone," Marijn van de Geer from XR said.

One of XR's long-term aims is for the UK to legally commit to reducing carbon emissions to net zero by 2025.

In January, the British arm of XR, which has previously closed key roads and bridges in London, blockaded oil refineries, smashed windows at banks and thrown paint over government buildings, said it would cease public disruption.

But other activists, such as Just Stop Oil, have continued with high-profile campaigns, including halting the World Snooker Championship.

While XR said this week's London action was not intended to be disruptive, nor would it target the coronation of King Charles next month, it intends to step up campaigns in "new and inventive ways," with possible "bigger disobedience."

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WHAT ARE THEY SAYING?

Clare Farrell, XR co-founder on The Big One: "This is about broadening the invite and bringing far more people in far more groups on board. For a lot of people, going on a march like coming to a picket is a first step."

Julia Hailes, climate activist for 35 years: "The Earth is dying. We have to stop this. People are becoming aware that we are facing a devastating future and we have a window of opportunity where we need to do something about it." 

Protester Lisa Milne, who had been hesitant about action that caused "friction" with the public: "I was happier to come along this time and join in and show support and show my concern for the planet and what we're doing to it."

TV wildlife presenter Chris Packham: "Our planet is in crisis and if we don't take action then we will not protect that life, which includes us."

London Mayor Sadiq Khan: "I hope there is no disruption by XR or anybody else."

HOW HAVE PROTESTS CHANGED?

The protests over the weekend represent a significant departure from previous XR demonstrations, which blocked parts of central London and saw hundreds arrested.

Climate protests in April 2019 featured a pink boat bearing the words "Tell the Truth," which was moored to the street for five days. Celebrities joined the protests with British actress Dame Emma Thompson saying "our planet is in serious trouble."

More than 680 climate change protesters were arrested and police eventually dismantled the boat before towing it away.

Last year XR protesters superglued themselves around the Speaker's chair in the House of Commons and padlocked themselves to the railings outside. Eight were arrested. 

However, earlier this year the group announced it would "temporarily shift away from public disruption" as a tactic to highlight its cause.

While XR promised it would not disrupt Sunday's London Marathon, Just Stop Oil declined to give such assurances. 

Following the protests at Saturday's horse racing in Scotland, Just Stop Oil tweeted: "Solidarity with those taking direct action at the Scottish Grand National today - civil resistance has, is, and will always be a justified method to demand the change we want to see."

Extinction Rebellion tweeted: "We share the streets and stand in solidarity with London Marathon runners, many running to raise money for nations already hit by the climate crisis."

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