Yoko blames Paul
In an interview with Sir David Frost for television channel Al Jazeera English, Paul said: ''She certainly didn't break the group up, the group was breaking up.''
Paul insists they were a number of different reasons why the band - which also included the late George Harrison and Ringo Starr - ended and he credits Yoko with inspiring some of John's best work.
The 'Hey Jude' songwriter believes the different creative influences Yoko, 79, brought into John's life helped him write tracks such as 'Imagine' and 'Dear Prudence'.
Paul said: ''I don't think he could have done that without Yoko, so I don't think you can blame her for anything. When Yoko came along, part of her attraction was her avant garde side, her view of things, so she showed him another way to be, which was very attractive to him.
''So it was time for John to leave, he was definitely going to leave [one way or another].''
However, Paul did admit that when Yoko started to sit in on The Beatles' recording sessions it had made him uncomfortable.
The bassist - who is married to Nancy Shevell - also admitted he still holds resentment against late businessman Allen Klein, and insists his attempts to take over the management of the band following the death of their manager and friend Brian Epstein in 1967 caused huge divisions between The Fab Four.
He said: ''I was fighting amongst the other three guys who'd been my lifelong soul buddies. I said I wanted to fight Klein.''
Although Paul has been regularly touring for the past several years to critical acclaim and released cover album, 'Kisses on the Bottom', this year, he hints he would ''like to retire soon''.