Lennon played guitar on the track

The track, a cover of the blues song Too Many Cooks recorded in 1974, featured Jagger on vocals, Lennon on guitar and Ringo Starr on drums, but was never released.

Auctioneers Cooper Owen said the unlabelled acetate - a record made directly from a master tape - had been "grossly underestimated" and was "worth up to �10,000".

It came on the market after Tom Fisher, a London record dealer, bought it for �20 four years ago from a man claiming to be a friend of Rolling Stones legend Ronnie Wood.

Mr Fisher, 34, said he was happy with the price, which came from an online bidder on Thursday.

"It's a pretty healthy mark-up, I can't really complain," he said.

"I'm quite happy about it, we are after all only talking about one record and there are plenty more records out there that I have yet to go out and buy."

The 10-inch (25cm) acetate had been described as "dynamite".

Star-studded session

Jagger is said to have personally verified it as genuine and said it was recorded while Lennon was estranged from Yoko Ono - the so-called Lost Weekend period.

According to Jagger, the track was recorded at a session called The Birthday Bash at the Record Plant studios in New York.

David Bowie and Lou Reed were also thought to have been present.

But he said he doubted that the acetate was worth much more than bootleg versions of the song that have been circulating for two decades.

In a message on his website, he said: "The song has been available as a bootleg for 20 years.

"I have no reason to think that the acetate in question has any more value than the other bootleg versions."