Now And Then - which was composed by John Lennon in 1978 and later worked on by Sir Paul McCartney, George Harrison and Ringo Starr when they reunited to work on the Beatles Anthology project in 1995 - never got released, but McCartney has been adding to it and is now keen for fans to hear the track.

A source said: "The Beatles song Now And Then is finished. All four Beatles are on the track. The original Beatles reunion version from 1995 was embellished with numerous sessions over the last two years by Paul McCartney.

"He wants the song to come out very badly."

As well as featuring Lennon - who was shot dead in 1980 - and McCartney on vocals, Harrison, who passed away in 2001, also sings backing vocals and plays guitar.

If the track does get a release it will be the first new Beatles song to come out since 1996's Real Love , which was composed by Lennon and later re-recorded by McCartney, Harrison and Starr with Lennon's original vocal part.

McCartney, 67, had also wanted to release the unheard Carnival of Light, a 14-minute composition, but Harrison was against the plans.