Sir Paul McCartney has revealed he was ‘so happy’ to have been reunited with his songwriting partner John Lennon before his friend’s untimely death.

McCartney and Lennon spent ten years together as part of the legendary Beatles, before splitting up in 1970 after a falling out.

But prior to Lennon being fatally shot by Mark Chapman in New York in 1980, the two resolved their differences and ended on good terms.

Speaking to Lennon’s son Sean on a BBC Radio 2 documentary, he said: "I always say to people, one of the great things for me was that after all The Beatles rubbish and all the arguing and the business, you know, business differences really… that even after all of that, I’m so happy that I got it back together with your dad.

“It really, really would have been a heartache to me if we hadn’t have reunited. It was so lovely too that we did, and it really gives me sort of strength to know that."

McCartney also spoke on the special show - which was to celebrate what would have been Lennon’s 80th birthday - about how he still wonders now what his former Beatle bandmate would have thought about some of his songs.

"I’m writing something and I go, ‘Oh god, this is bloody awful’, and I think, ‘What would John say’?

"And you go, ‘Yeah, you’re right. It’s bloody awful. You’ve got to change it’.

“And so I’ll change it, and I know from reports that he did similar things to that. If I’d have a record out, he’d go, ‘Bloody hell… got to go in the studio. Got to try and do better than Paul’.”