HE is the world famous guerrilla graffiti artist who swoops secretly in the night to splash urban landscapes with his edgy paintings.

His anti-establishment work sells for up to £1m and his celebrity fans include Angelina Jolie and Brad Pitt. Now, the world’s most elusive aerosol painter Banksy has left his mark on a Southampton street wall in the middle of the night. Bristol-born Banksy, whose true identity remains secret, has sprayed a piece of his art work in Bevois Valley.

It has been painted on the 6ft white garden wall of a privately-owned terraced house.

Experts estimate the work would be worth more than £20,000 and that does not include the cost of putting up a new wall. Dozens have already travelled to take photos of the eye-catching drawing of a monochrome young boy who appears to be sat on a pavement holding a balloon with the words “No Future” in red letters above.

It is believed the urban warrior sprayed his iconic stencil en route to the Isle of Wight.

Although the art has been there for a number of weeks it has only just been confirmed as the work of the famous spray painter.

Keith Sekree, owner of TAOI Gallery in Shamrock Quay, who displays Banksy originals, said the work will make the city more vibrant.

The art dealer, said: “It is really unusual for him to do such a random piece. Usually there is a point to him being there. It is the first time he has been to Southampton and it is fantastic for the city.

“One of the most sought after artists of a generation has spent his time painting something which really should be preserved for people to see and appreciate.”

Mr Sekree, added: “The piece in Southampton is a great one, it encapsulates so much of what Banksy is good at. The message is linked to his famous Girl With Balloon via the red balloon making up part of the slogan.”

Local councillor for Bevois and Labour arts spokesman, Derek Burke added: “It’s fabulous that Banksy’s been to Bevois and left his mark. It might be a springboard to add some life into what is a run-down area and get people flooding into the city.

Last night, Southampton City Council confirmed they would not be removing the work.

Leader Councillor Royston Smith said: “The graffiti was done on a private wall and naturally we would let the owner decide what they want to do with it. The council would therefore not protect the work.”