The Metropolitan Police said on Nov. 22 that 30 people were held at Lambeth Bridge and another 94 at Vauxhall Cross near Vauxhall Bridge when the roads were blocked by demonstrators on Saturday.
Insulate Britain said the action was taken to deliberately break the legal ban on supporters blocking roads and causing traffic chaos.
The group has provoked anger among motorists with a series of stunts blocking motorways in recent months.
But it has insisted that its protests will continue “until the Government issues a meaningful statement to get on with the job of insulating Britain’s leaky homes”.
The High Court has so far issued five injunctions to prevent protesters from blocking roads.
They include four injunctions granted to National Highways, banning demonstrations on the M25, around the Port of Dover and on major roads around London, and one to Transport for London (TfL).
TfL was granted a civil banning order aimed at preventing protesters from obstructing traffic on some of the capital’s busiest roads.
Those who breach the injunctions could be found in contempt of court and face a maximum penalty of two years in prison or an unlimited fine.
Nine Insulate Britain activists have already been jailed after admitting taking part in a blockade at junction 25 of the M25 during the morning rush hour on October 8.
Further legal action is expected to be taken against protesters involved in similar demonstrations on October 27.