In his latest interview, Sir Paul was questioned about the sophisticated compositions of many Beatles’ songs, which have drawn praise from experts on classical music.

Asked whether the band worked from a “broader range of musical language” than others such as the Stones, he replied: “I’m not sure I should say it, but they’re a blues cover band, that’s sort of what the Stones are. I think our net was cast a bit wider than theirs.”

It comes after Sir Paul this week blamed John Lennon for the demise of The Beatles in a separate interview with the BBC.

Sir Paul has often been viewed as the driving force behind the band’s split in 1970 after he revealed in a press release for his solo album that he was on a “break” from them.

But he told a forthcoming episode of BBC Radio 4’s This Cultural Life: “I didn’t instigate the split. That was our Johnny. John walked into a room one day and said ‘I am leaving the Beatles’. And he said: ‘It’s quite thrilling, it’s rather like a divorce.’ And then we were left to pick up the pieces.

“The point of it really was that John was making a new life with Yoko and he wanted … to lie in bed for a week in Amsterdam for peace. You couldn’t argue with that.

“It was the most difficult period of my life. This was my band, this was my job, this was my life, I wanted it to continue. I thought we were doing some pretty good stuff – Abbey Road, Let It Be, not bad – and I thought we could continue.”