The piano on which John Lennon composed his peace anthem Imagine is to be auctioned for an estimated �1m - a record price for pop memorabilia.

The upright Steinway will be sold in July on the entertainment memorabilia website eOffer online, which is being set up by Fleetwood Mac star Mick Fleetwood and auctioneer Ted Owen.

The website itself does not launch until March, and the piano is currently on display at The Beatles Story museum at Liverpool's Albert Dock.

Although the piano is not the famous white one featured in the Imagine video, it was kept by Lennon in his Ascot home and was used to both compose and record his legendary hit.

Mr Owen said that he expected the piano to go for a record-breaking amount due to both the popularity of Imagine and the overall importance of the former Beatle's work.

"The memorabilia market has recently shown some spectacular results, with Eric Clapton's guitar going for �500,000 recently.

"But John Lennon is a far greater influence globally, spiritually and musically. Our valuation is based on the previous interest we have seen and seems to be in keeping with what people expect."

Public affection

Imagine, originally recorded in 1971, was a number one hit when it was re-released shortly after Lennon's death in 1980.

More recently, the song was voted the UK's favourite lyric in a poll last year and the second greatest song of the millennium.

Public affection for it led to another re-release just before Christmas, when it went to number three in the charts. The album of the same name was reissued on Monday.

Steinway are said to have authenticated the walnut piano, and say footage from 1971 shows Lennon at the keys composing Imagine.

The instrument is currently owned by a private collector from southern England, who has asked that it remain on display in Liverpool until October.

Mr Owen explained: "He (the owner) feels, like we do, that it needs to be in a museum and that's why it's being shown at the Beatles museum until 9 October, which would have been Lennon's 60th birthday.

"If he were American it would be kept somewhere as part of their national heritage, and I think it's about time that the British took that approach.

"We would like to see some national body or museum putting money forward to buy it."