Climate protesters on Monday blocked a major UK motorway at a road leading to London's Heathrow Airport.
The activists, who are demanding that the UK take action on home insulation, defied an injunction won by the government last week preventing them from occupying roads.
The interim ruling gave police the authority to imprison Insulate Britain's protesters after the authorities were criticised for being soft on earlier protests.
A similar injunction was granted on Saturday, prohibiting the occupation of the A20 and other arterial roads linked to the Port of Dover. It came after Insulate Britain protesters blockaded the area on Friday.
The group's tactics have made it something of a pariah in the UK, yet spokeswoman Tracey Mulligan said its all-publicity-is-good-publicity strategy had "certainly got everybody talking about insulation".
"We have got people considering that our government is legally failing in their duty to protect us and I think we're showing that [UK Home Secretary] Priti Patel, unfortunately, is trying to scare us with an injunction and that shows her lack of character, not ours," she told LBC radio.
"You can't put an injunction on hunger, you can't put an injunction on physics, and we are terrified for our children's future and sick of over 8,000 people dying each year from the choice of heating or eating."
She admitted that the group was not happy about the injunction but highlighted what she called "the bigger context".
"We are tired of over seven million people having to choose between heating or eating and we know that's going to get worse with the energy crisis that we're facing now."