Just Stop Oil has threatened to slash famous artworks and “escalate” their efforts in the run up to Christmas.
The activist group has also called on England striker Harry Kane to wear a captain’s armband carrying their message at the World Cup in Qatar for the remainder of the tournament.
London galleries will be wary of the threat, with Just Stop Oil having already thrown soup at Van Gogh's Sunflowers painting inside the National Gallery and glued themselves to frames of other masterpieces. Activists Hannah Hunt and Eden Lazarus will next week face trial accused of causing criminal damage to John Constable's The Hay Wain, after a video showed the pair glueing themselves to it.
Their forthright and sometimes controversial tactics have also seen the group glue themselves to tarmac on busy roads and scale motorway infrastructure, bringing traffic to a standstill.
While detractors have called the group’s actions “moronic”, Just Stop Oil spokesman Alex De Koning said: “[It is] insane that more people are outraged,” by their protests than other world crises - such as the floods in Pakistan.
The 24-year-old self-identified “climate scientist” said he wants Just Stop Oil to follow in the footsteps of Suffragette Mary Richardson who attacked Diego Velazquez's painting The Rokeby Venus with a meat cleaver in 1914 after Emmeline Pankhurst was arrested.
Mr De Koning told Sky News: "If things need to escalate then we're going to take inspiration from past successful movements and we're going to do everything we can.
"If that's unfortunately what it needs to come to, then that's unfortunately what it needs to come to. We're fighting for our lives, why would we do any less?"
He then added about potentially slashing paintings "It could potentially come to that at one point in the future, yeah”.
The Sunflowers are unlikely to have permanent damage because of the gloss protecting the masterpiece although Mr De Koning has said he does not enjoy the means of opposition.
"It's obviously terrible,” he said of defacing art. “Yes, of course, we don't want to be doing things like that.
"The question you need to be asking is why on earth would students, grandparents, engineers, doctors, nurses, do something like that? It's because our government is behaving criminally."
He added about England captain Kane, “A lot of people really respect [him]... so a lot of people would be swayed by [him wearing a Just Stop Oil armband]."
