London - Paul McCartney wants to release an obscure 41-year- old Beatles track that was only played once in public, Britain's Observer newspaper said Sunday.

The 14-minute Carnival of Light was recorded in 1967 when Paul, Ringo Starr, George Harrison and John Lennon were working in London's Abbey Road studios on the vocals for Penny Lane.

The track, a jumble of shrieks and psychedelic effects, was never released because three of the Fab Four thought it too adventurous.

To enable it to be made public McCartney needs the approval of Ringo, as well as the widows of Lennon and Harrison, Yoko Ono and Olivia.

McCartney had been commissioned to create the piece for an electronic music festival. He asked the other Beatles to wander around the studio and play a few notes on the piano, drums and other instruments.

What turned out was was a mix of strangled shouts from Lennon which vie with church organs and distorted guitar, noting all all like the melodious sounds the group is known for.

The song was played only once, at the Million Volt Light and Sound Rave in London's Roundhouse theatre. Many in the audience had no idea they were listening to a new Beatles track.