Insulate Britain demonstrators burned their court orders banning their road-blocking protests outside the Royal Courts of Justice, as a High Court judge extended the injunctions until the end of next month.
Members of the Extinction Rebellion offshoot have repeatedly blocked major roads, including the M25 and the M4, since September 13.
In response, National Highways has been granted three injunctions banning the demonstrations on the M25, around the Port of Dover and on major roads around London.
At a second public High Court hearing on Tuesday, the three injunctions were extended until November 30.
National Highways’ barrister David Elvin QC said the demonstrations are “dangerous and disruptive” in written arguments.
“They create an immediate threat to life, putting at risk the lives of those protesting and normal motorway users, as well as those reliant on the movement of emergency services vehicles to protect the public and save lives,” he added.
During Tuesday’s hearing Insulate Britain members were given the chance to argue against the injunctions.
One demonstrator, Liam Norton, told the court: “I just want to say publicly Insulate Britain are in the process of trying to uphold the law, the UK Government has a responsibility to keep temperatures below 2C degrees.
He added: “Boris Johnson should be on trial for treason.”
Mr Norton later asked why there had been a delay in proceedings and whether this was related to the Cop26 talks in Glasgow, due to begin on October 31.
Mr Elvin told the court that any delays were due to issues in serving the court orders on the demonstrators.
He added: “It may well be committal proceedings are initiated sooner rather than later.
“It should not be inferred that anyone is going to wait until after Cop to issue committal proceedings.”
Breaching a court order can result in a committal for contempt of court, which if proved may be punished with up to two years in prison and an unlimited fine.
During the hearing, other members of Insulate Britain were outside the Royal Courts of Justice in London and were seen burning papers.
Nick Onley, 59, a food bank worker and community musician from London, told the PA news agency: “The papers that are being burned are the front covers of the injunctions that have been served on us as individuals.
“It’s a sign of our determination to carry on protesting, to carry on raising this issue until we see some action that we can believe in”.
According to court documents, 112 people have been served with court orders related to the Insulate Britain protests.
When asked about criticism of the group, Mr Onley said: “Doing this protest in the last month is probably the most horrible thing I’ve done in my life.
“But we feel that we’ve been put in a position where unless protests cause serious disruption they are just not going to be taken any notice of.”
Mr Elvin later indicated that National Highways may ask for a default or summary judgment – legal steps which would mean the case against the protesters is resolved without a trial.
Mr Justice Lavender said that he would extend the three injunctions but was “reluctant” to make orders with no end date.
A fourth injunction was granted to Transport for London (TfL) on October 8.
National Highways and TfL will now return to the High Court on October 19 for a further hearing.