Sir Paul McCartney has revealed that he wrote the Beatles hit 'Yesterday' in a dream.

The song was originally recorded for the band's 1965 'Help!' album and is in the Guinness Book of Record for having the most cover versions.

Sir Paul spoke about the origins of the song after he was asked to name his favourite Beatles track during a radio interview on XFM.

He said: “One of mine? If I had to answer one song it would have to be ‘Yesterday’ because it came to me in a dream and because 3000 people are supposed to have recorded it.

“That was entirely magical – I have no idea how I wrote that. I just woke up one morning and it was in my head. I didn’t believe it for about two weeks”.

The first cover version of 'Yesterday' charted in the UK top-10 just three months after the band released 'Help!'.

You can see a selection of rare Beatles shots from CBS’ exhibition, which is on display at the Beatles Story until November, below...