Rush hour traffic has been brought to a standstill on the M25 after protesters climbed onto gantries across at least six different locations, a campaign group claimed.
Activists from Just Stop Oil climbed onto overhead gantries with police having to halt traffic on both clockwise and anti-clockwise carriageways.
Matt Twist, Assistant Commissioner at the Met Police, said the force has reports of up to nine junctions on the M25 where activists were trying to cause "serious, unlawful and unreasonable disruption".
Officers from across the southeast swarmed the scene and were dealing with the incident, he added.
An activist has also climbed a gantry on the M25 in Surrey.
Police are at the scene on the clockwise carriageway between Junction 6 (Godstone) and Junction 7, having first been called at around 7.40am.
The disruption comes despite National Highways successfully getting a High Court order that bans the climate change group from disrupting the country's busiest motorway.
This means that anyone fixing themselves to any object or structure on the motorway - and anyone assisting - can be held in contempt of court.
Those in breach of the order could face imprisonment, an unlimited fine and seizure of assets.
Surrey Police has also added that it has received reports of protesters on the motorway gantries between junctions 8-9, one between junctions 13-12 southbound and one between junctions 13-14.
"We are here and dealing and will get this resolved as soon as possible. Thank u (sic) for your patience," the force said in a tweet.
The force added that the decision was made to close the road “for the safety of everyone” while officers attempted to remove the activists.
And a protester also targeted junction 30 of the major motorway circling London, with Essex Police urging the public “not to intervene”.
The force tweeted: “We are currently responding to reports of people climbing up an overhead gantry close to Junction 30 of the M25.
“Arrests have been made already.
“We are dealing robustly and ask the public not to intervene.”
In a press release, the Just Stop Oil group, which is campaigning against the Governement's new oil and gas licence plans, said it contacted the Metropolitan Police and National Highways last night to warn them of this morning's disruption.
Indigo Rumblelow, 28, a spokesperson for Just Stop Oil from London said: "What did you expect? This government is complicit in an illegal and unconstitutional plan to issue more licenses and consents for new oil and gas.
"A plan that will take the world over 1.5C, resulting in the collapse of ordered society, the loss of our rights and freedoms and the death of millions of people.
"Our latest Prime Minister Rishi Sunak talks of the importance of ending our dependence on fossil fuels yet he is still planning to allow new fossil fuel projects.
"This is a failure of politics. People have the legal right under British law to cause disruption to prevent a greater harm: the right of necessity. We do not do this lightly.
"After thirty years of public debate, lobbying and petitioning, and three years of peaceful civil disobedience, we are still on course for catastrophic climate breakdown and we have nowhere else to go. The government is doubling down on fossil fuels, indicating ever greater levels of criminality."
The campaign group adds that since their campaign began on April 1, Just Stop Oil supporters have been arrested nearly 2,000 times with six activists currently in prison.
Last night, the Met Police launched a “significant” operation to identify and arrest climate change protesters suspected of planning “reckless and serious” motorway disruption as Cop27 gets underway in Egypt.
Mr Twist said three people were arrested yesterday evening who were suspected of planning public disruption. Police were expecting to make more arrests overnight.
Mr Twist said: “Our investigation has strong reason to suspect the Just Stop Oil group intend to disrupt major motorway road networks which would risk serious harm to the public, with reckless action to obstruct the public on a large scale.
“All those arrested are suspected of engaging in conspiracy to cause public nuisance contrary to Section 78 Police, Crime, Sentencing and Courts Act 2022.
“There remains a possibility outstanding suspects are still intent on causing unlawful disruption to the public. The Met has mobilised specialist teams and drawn police officers from across the capital to respond.”
According to the Met, which is conducting the operation in conjunction with the National Police Coordination Centre (NPoCC), more than 10,000 officer shifts have been dedicated to policing Just Stop Oil protests since the start of October.
Police are calling on the public to assist with preventing public disruption from protesters by reporting it to 999.
Just Stop Oil staged 32 days of disruption from the end of September and throughout October, which the Met said resulted in 677 arrests with 111 people charged, and officers working a total of 9,438 additional shifts.
The climate change action group has been calling on the Government to abandon plans to licence over 100 new oil and gas projects by 2025, and to do more to help people with their skyrocketing energy bills.
