Sir Paul McCartney is thankful he got to reunite with John Lennon before his passing

McCartney was "so happy" to get back together with Lennon and to patch things up between them after the 'Come Together' group - which was also comprised of Sir Ringo Starr and the late George Harrison - went through a difficult split 10 years earlier.

Speaking to Lennon and Yoko Ono’s son Sean Ono Lennon for BBC Radio 2’s 'John Lennon at 80' series, McCartney 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.”

The 78-year-old music icon compared The Beatles' breakup to a “divorce”, but insisted the end of the band wasn't as "gloomy" as he thought.

When Sean asked about their film 'Let It Be', which was released the same year they split, he said: "You know what I think it was, I think it was the fact that The Beatles were breaking up, which was a very difficult time for us, it was like a divorce, you know. So it's very difficult to collect your thoughts and to just be jolly. And by the time 'Let It Be' came about that became the story of the film. And then that coupled with the fact that we’d broken up, left it a gloomy, left sort of cloud in the room, and I'd always bought into that. So for years when people say, ‘Oh,’ about 'Let It Be' I go, ‘Yeah, you know, I didn't really like it because it was such a gloomy period.’ But then talking to Peter Jackson, when he was looking at the 58 hours of outtakes, I said, ‘Well, what's it like?’ kind of thing, expecting him to say, ‘Well, it's very gloomy. You're all arguing all the time.’ He says, ‘No’, he said exactly what you just said. He said, ‘It's amazing. You're like jolly and stuff.’ And he showed me some bits. And it's just great. It really made me happy. Because I know, for years there, I thought ‘Oh God, The Beatles broke up, and it was acrimonious and we were arguing and oh’, which happens in a divorce, you know?"

Listen to 'John Lennon at 80' from 9-10pm, Saturday 3rd and Sunday 4th October on BBC Radio 2 and BBC Sounds.