Just Stop Oil supporters are protesting on the M25 for the fourth consecutive day.
Surrey Police said officers are dealing with activists who climbed a gantry at Junction 8 of the UK’s busiest motorway.
The road is closed anti-clockwise.
Essex Police said it arrested a woman attempting to climb a gantry around 1.5 miles from Junction 28 clockwise.
The force said: “One lane was closed for a short time as officers responded to the situation.”