British police arrested 39 people on Friday during a climate protest at the Dover port which slowed activity.
The British government has announced it is seeking a legal injunction against protestors who blocked the entrance to Europe's busiest ferry port on Friday to urge authorities to do more against climate change.
Vehicles remained stuck in lines as more than 40 activists from the group Insulate Britain blocked the main road into the Port of Dover, which handles 17% of Britain's trade in goods.
Transport Secretary Grant Shapps said authorities "won't tolerate reckless behaviour on motorways or ports (Dover this morning)", as he announced action to prevent further disruption.
The protest group, which already blocked London's M25 highway for five days in September, apologised for the disruption but added it was "the only way" to keep the insulation issue on the agenda.
They also denounced that "poorly insulated homes are causing ill health, misery and early death" for thousands of people.
The group believes better insulation of UK homes would cut emissions as well as energy costs.
The British government already has a court injunction against the highway protesters, meaning the group's members could be jailed if they block the M25 again.
Several climate activists, many of them students taking time out from school, staged rallies around the world on Friday to call for tougher action on climate change.