A section of wall containing a Banksy graffiti mural is being stored in the north of England by private collectors and may never return to the area.

The spray-painted Banksy picture on the border of Croydon and Sutton, depicting a punk-rocker putting together a flat-pack IEAK graffiti slogan appeared on a wall in Beddington Farm Road last year.

Sutton Council is looking for a private benefactor to purchase the piece after collectors, Bradley Ridge and Nick Loizou, spent more than £30,000 having the three-tonne mural excavated and renovated after it was targeted by vandals.

The restaurateur and his graphic designer friend bought the wall hoping it would fetch £500,000, but have been unable to get the image certified because the artist has refused to officially recognise it as his.

Councillor Sean Brennan, leader of Sutton Council, said: “The Banksy artwork really caught the imagination of people in Sutton and when it appeared we ran a straw poll to find out what residents thought should happen to it.

“We had hundreds of emails with over 90 per cent in favour of keeping and preserving it so we are disappointed that it has been removed and is now being sold.

“It would be great if a private benefactor from Sutton was able to bid for it and bring it back to the borough.”

An in-house authentication team set up by the elusive artist, Pest Control, has refused to confirm it as Banksy’s, despite the mural appearing on the artist’s website.

Talking to Channel 4 news, Mr Ridge, said: “I’d like £10m for it but I think it is worth half-a-million pounds. We drove past it three times and missed it because it was so badly defaced and tagged. It suddenly hit you it was there, it was a bloody great Banksy.”

The pair worked night and day for 10 days to excavate the piece which was a harder task than they initially thought – the wall turned out to be nine-inch-thick reinforced concrete.

Mr Ridge said: “It was an absolute pain to get out. I swallowed my heart when it was going up, I was in silence.

“You definitely can’t auction the piece off. I spoke to someone at Sotheby’s before we had actually taken the wall out and he said it’ll never sell without authentication.”