The tens of thousands of Indians heading towards London now that summer is not too far away should look out for the new Banksy mural in Marble Arch after they have done their traditional shopping in Oxford Street.

Banksy used the chaos caused by “Extinction Rebellion”, the climate change protesters who have disrupted traffic in Marble Arch, Waterloo Bridge and Parliament Square over the past 10 days, to slip in and put up his new art work without being spotted.

The protesters claim that the artist clearly supports their cause because the image he has stencilled shows a child clutching an Extinction Rebellion sign while crouching near a plant shoot emerging from the earth.

“From this moment despair ends and tactics begin,” the accompanying words say.

Experts are pretty convinced this is a genuine Banksy and so is the local authority, which is being characteristically progressive and wants to retain the mural rather than erase it as nuisance street graffiti.

Westminster City Council leader Nickie Aiken said: “Banksy’s work always generates excitement. We believe it’s genuine and are working to confirm that it is the case. This street art has clearly captured the public mood and imagination, and so we’re looking to keep it in a public place for people to enjoy.

“The piece will act as a daily reminder to all of us of the need to work together to protect our planet, particularly when the concerns of climate change are very much in the news. Our officers have been working hard all day, looking into the best way to protect it in the short term while we explore permanent options.”

Extinction Rebellion supporter Calvin Benson, 48, from north-west London, said: “This artwork represents the will of the people that were here and the people of the nation.” Asked whether this was a Banksy original, he responded: “One hundred per cent it’s a Banksy. It’s already been confirmed by street artists and the whole community knows about this. Read the message — he’s a supporter of Extinction Rebellion.”

Banksy is now a cult figure whose work has fetched over a million dollars at auction. For those unfamiliar with his modus operandi, he is a sort of Scarlet Pimpernel of the art work whose identity is not known though there have been guesses.

He is described as “an anonymous England-based street artist, vandal, political activist and film director. His satirical street art and subversive epigrams combine dark humour with graffiti executed in a distinctive stencilling technique. His works of political and social commentary have been featured on streets, walls, and bridges of cities throughout the world.”

Narendra Modi should consider himself lucky he hasn’t made a trip to India – he would be perfect for a political city like Calcutta.