The two activists defaced the front of the luxury jewellers in Knightsbridge at around 8.30am, the group said.

It comes after three weeks of daily protests, which have included climbing 200ft above the Dartford Crossing and people gluing themselves to several roads.

Adrian Johnson, 56, a former deputy headteacher from Perthshire in Scotland said: "The science is clear. The breakdown of the climate is here and it is due to the extraction and use of fossil fuels. Any new fossil fuel projects will cause irreparable damage to the climate. This may have already happened.

"And yet, this is the path our government is following by granting over 100 new oil and gas licences. It makes no sense and it's reckless beyond belief."

Jennifer Kowalski, 26, an environmental scientist from Glasgow, said: "People around the world are starving, suffering and dying so an elite can spend vast fortunes on vanity items."

Just Stop Oil wants the government to suspend all new fossil fuel licences.

The Met Police said they were "quickly on the scene" by 8.43am and arrested two protesters on suspicion of criminal damage.

"They have been taken into custody at a central London police station," a spokesperson said.

New PM reinstates fracking ban

It comes as new Prime Minister Rishi Sunak has reversed his predecessor Liz Truss's decision to lift the moratorium on fracking.

New oil licences have been granted in the North Sea, however.

Read more:
Just Stop Oil vow to keep causing disruption
Bob Geldof says Just Stop Oil protests are 'clever'

Speaking to Sky News, Professor Lorenzo Fioramonti, director of the University of Surrey's Institute for Sustainability, said the group's "strategies are backfiring".

They also risk "dividing the ecological front" and "tainting the cause" of groups who are engaged in constructive dialogue with governments, fossil foil producers and big business, he added.