Extinction Rebellion activists are launching legal action against the police in England over a London-wide ban on their protests.
The move comes amid growing criticism of the ban, made under public order legislation already used to restrict the action to Trafalgar Square.
Activists continued protests in the capital in defiance of the police order, targeting the Department for Transport and locking themselves to a caravan on Millbank.
Human rights lawyer Tobias Garnett, working for Extinction Rebellion, said the group would be filing a High Court claim challenging the ban on the grounds it is “disproportionate and unlawful”.
The group was planning to file a claim on Tuesday afternoon, and was seeking an expedited hearing.
Mr Garnett said the police order limiting protests “risks criminalising anyone who wants to protest in any way about the climate and ecological emergency that we face”.
Under the current order, any assembly – classed as a gathering of two or more people – linked to Extinction Rebellion in London is unlawful.
Lawyers have questioned the legality of ban, aimed at halting further protests after more than a week of disruption by the environmental activists in London, while a number of politicians expressed outrage over the move.