The campaign group, an offshoot of Extinction Rebellion, has asked that if drivers do use the road they reduce their speed to 20mph.
They said: “Starting from 7:00 on the morning of Wednesday October 27, the M25 will become a place of nonviolent civil resilience to stop our Government committing crimes against humanity.
“We ask that: People do not use the M25, and if they do, speeds are reduced to 20mph to minimise the risk of accidents.”
Insulate Britain also called on the Highway Agency to enforce the 20mph speed limit it had set and asked the police to “refuse to arrest us”.
‼️“WE DECLARE THE M25 A SITE OF NONVIOLENT CIVIL RESISTANCE”‼️
🕊 "... on the morning of Wednesday 27th October the M25 will become a place of nonviolent civil resistance to stop our government committing crimes against humanity."
Read below 👇https://t.co/HNHfxEeG22
— Insulate Britain (@InsulateLove) October 26, 2021
In return for their demands, the climate activists said they would ensure emergency access is maintained.
But a spokesperson for Highways England has said that changing the speed limit ahead of an incident “creates a far greater risk to the wider travelling public”.
National Highways Regional Director Nicola Bell said: “Our road network is integral for our customers’ journeys and is the backbone of the country’s economy; connecting people, building communities and helping people go about their daily lives.
“Our primary concern is always safety, but changing speed limits in advance of any incident creates a far greater risk to the wider travelling public.”
The Metropolitan Police said: “The Met has a comprehensive policing plan ahead of a threat of protest action by environmental group Insulate Britain on Wednesday October 27.
“Officers in London are working closely with neighbouring policing forces in order to respond swiftly to any protest action on respective road networks.”
Transport Secretary Grant Shapps said the protesters were “back, risking lives and ruining journeys” after activists brought the streets of the City of London and Canary Wharf to a standstill on Monday morning.
The Metropolitan Police said 52 demonstrators had been arrested after the roadblocks in east London.
Insulate Britain are calling on the Prime Minister to “lead our country through the climate crisis”.
They say: “The UK government must immediately promise to fully fund and take responsibility for the insulation of all social housing in Britain
“We demand a national home insulation strategy that gives British people the justice they deserve: a future for our loved ones, lower energy bills and safer living conditions.
“We are scared: our livelihoods are at risk and the futures of our children are uncertain. The Climate Crisis is a threat to all: we demand the Government act now.”