The UK campaign group Just Stop Oil on Tuesday said activists had glued themselves to a painting at the Royal Academy in London, in the fifth such protest in a week.
Four people from the direct action group sprayed paint under and stuck their hands to "The Last Supper" – a full-scale copy of Leonardo Da Vinci's famous work – dating from circa 1520.
On Monday, two supporters of Just Stop Oil glued themselves to John Constable's "The Hay Wain" at the National Gallery in central London.
Last week, three other paintings, including one by Vincent van Gogh, were targeted at other galleries in London, Manchester and Glasgow.
Just Stop Oil wants the UK government to end approval of new oil and gas licences.
One of those involved in Tuesday's protest, former primary school teacher Lucy Porter, 47, from Leeds, northern England, said the campaign would continue unless the government changed its policy.
Fellow activist Tristan Strange, a 40-year-old community organiser, added: "Da Vinci said that art is the queen of all sciences, communicating knowledge to all the generations of the world.
He added: "The science still isn't being heard."
Police earlier announced that six Just Stop Oil protesters were charged with conspiracy to cause public nuisance after invading the track at the start of the British Grand Prix on Sunday. (AFP)