Sir Paul McCartney has admitted that he struggles to remember how to play most of his songs.

The former Beatle said he had written almost 300 songs in The Beatles and could only “conjure up” a select few tracks if asked to perform an impromptu set.

"I know my songs when I go tour because I learn them to go on tour, but actually I think there's just too many of them for me to retain them so I don't know them all,” he said.

Sir Paul added: ‘If I’m at a party and there’s a piano I would do ‘Long and Winding Road’, 'Lady Madonna', 'Blackbird' - there are certain ones that I can just conjure up.

“But, really, the truth is people say 'go on, do that one' but I have no idea how it goes."

Sir Paul was speaking at a press conference in Washington ahead of being presented with The Gershwin Prize for Popular Song by the Library of Congress.

He also told reporters that the ongoing Gulf Coast oil spill was "a disgrace".

(by Jason Gregory)