Activists from Insulate Britain want the government to commit to providing insulation for 29 million homes. Over five days of protests so far they have blocked slip roads, glued themselves to the road and poured paint onto the carriageway.

The agency which manages Britain’s roads was granted a court order late on Tuesday meaning that protesters could face imprisonment, transport minister Grant Shapps said.

“Invading a motorway is reckless & puts lives at risk. I asked National Highways to seek an injunction against M25 protestors which a judge granted last night,” Shapps said on Twitter.

“Effective later today, activists will face contempt of court with possible imprisonment if they flout.”

Angry motorists and business owners have complained the protests were stopping people from getting to work and causing missed hospital appointments. Police have made dozens of arrests.

The group has defended the disruption, which it calls civil disobedience, saying it is essential to get the government to take notice.