Paul McCartney often dreams about his former The Beatles bandmate John Lennon.

The pair made up the Fab Four alongside Ringo Starr and George Harrison. The music legend, 77, revealed during an appearance on The Late Show with Stephen Colbert on Monday night that he still has dreams about the late Lennon "quite often" - nearly 39 years after the musician's death.

"I dream about him," McCartney shared. "When you've had a relationship like that for so long, such a deep relationship, I love when people revisit you in your dreams. I often have band dreams and they're crazy. I'm often with John... I have a lot of dreams about John. They're always good."

The pair both lost their mothers at a young age, and the Let It Be hitmaker explained the tragedy drew them close to one another, and played a key role in the direction of one of their biggest hits, Yesterday.

"We both knew about that. We both knew that feeling," he mused. "I never thought it affected my music until years later. People were saying, 'Well that song, Yesterday... 'Why she had to go, I don't know, she wouldn't say?' They said, 'That's your mum.' I said, 'I don't know.' I certainly didn't mean it to be. But it could be. Those things can happen."

McCartney, along with surviving bandmate Starr, is celebrating 50 years since the release of the band's seminal Abbey Road album, which has been remastered and will be reissued, along with 23 bonus recordings and demos, a collection released on 27 September.