Paul McCartney sat down with David Frost recently for an hour long interview in which he said that the Beatles were breaking up regardless of anything Yoko Ono did or said.  McCartney did go on record as saying that Ono's presence in the studio during some of the group's last recording sessions made him uncomfortable, but added that manager Allen Klein, the man that took over managing the group after Brian Epstein's death in 1967, was a far more detrimental to the band, a statement he punctuated by pretending to punch a photo of Klein.  According to Paul, Klein was the one that caused him to start feuding with John, George and Ringo, telling Frost, 'I was fighting against the other three guys who'd been my lifelong soul buddies. I said I wanted to fight Klein.'
He also gave credit to Ono for having been an inspiration to John, pointing out that without her Lennon would never have written Imagine.
Guardian.co.uk

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