Just Stop Oil activists have shut down sections of the M25 by climbing onto gantries along the motorway during rush hour.
A stretch of road between Junctions 6 and 7 in Surrey and the key Junction 25 in Waltham Cross were closed as police dealt with demonstrations on Monday morning.
Activists also targeted other locations along the motorway circling Greater London in a call to end all new oil and gas licenses.
It came after police made a number of arrests over planned protest activity along the motorway network.
Have you been affected by Just Stop Oil? Get in touch with zoe.tidman@independent.co.uk
Surrey Police said National Highways decided to shut a stretch of road between Junction 6 and 7 “for the safety of everyone” while officers attempted to remove the activist from an overhead gantry.
The activist was brought down around 8.40am - around an hour after the force first shared an image of the protester on the motorway structure at Junction 6.
Surrey Police said it was also dealing with activists on motorway gantries between Junctions 8 and 9, Junctions 13 and 12 southbound and Junctions 13 and 14 on Monday morning.
“We are here and dealing and will get this resolved as soon as possible. Thank u for your patience,” it tweeted.
The Metropolitan Police said a protester had also climbed onto a motorway gantry at Junction 25 on the M25, also known as the Waltham Cross Interchange, around 8am.
The road was temporarily closed anticlockwise.
Just over an hour after its first tweet, the Met said the activist had been removed from the gantry.
Essex Police was also responding to reports of a protester on an overhead gantry at Junction 30 of M25.
“Arrests have been made already,” the force said. “We are dealing robustly and ask the public not to intervene.”
Just Stop Oil shared a video from the viewpoint of a motorway gantry on its social media on Monday morning.
The climate action group said its supporters had climbed onto structures along the M25 “at multiple locations” and caused traffic to grind to a halt in its call for the government to end all new oil and gas licenses.
It also shared a video of a tearful protester taking part in the demonstration.
“I’m here because I don’t have a future,” the young woman said. “You might hate me for doing this, but I wish you would direct all that anger and hatred at our government.”
On Monday, a minister said any Just Stop Oil protesters causing M25 closures deserved to spend Christmas in prison.
“It’s completely wrong to disrupt people’s lives this way,” business secretary Grant Shapps said, adding: “I hope that justice is served up to these people.”
On Sunday, the Met said it had carried out an investigation that gave it “strong reason” to suspect Just Stop Oil was planning to “disrupt major motorway road networks”.
Assistant Commissioner Matt Twist said three arrests were made that evening, although police would continue working on the operation overnight.
