It's been more than 50 years since Paul McCartney announced The Beatles were going their separate ways and, in a new interview, the rock legend discussed who actually was responsible for initiating the breakup.

"I didn't instigate the split. That was our Johnny," McCartney, 79, said regarding the late John Lennon when talking to BBC Radio 4's "This Cultural Life." The Guardian obtained an advanced copy of the special, which is scheduled to air Oct. 23.

He recalled, "John walked into a room one day and said, 'I am leaving The Beatles.'"

McCartney said ending The Beatles was a difficult pill to swallow that led to "the most difficult period" of his life. He said he and bandmates Ringo Starr and George Harrison were "left to pick up the pieces" by being forced to keep Lennon's exit a secret.

"So for a few months we had to pretend. It was weird because we all knew it was the end of The Beatles, but we couldn't just walk away," McCartney told the outlet.

The pressure eventually got the best of him. He said he became "fed up of hiding it" and admittedly "let the cat out of the bag" when promoting his debut solo album "McCartney" in April 1970.

McCartney also reflected on the infamous lawsuit he brought against his bandmates, saying it was because he didn't want to be controlled by manager Allen Klein.

"I had to fight, and the only way I could fight was in suing the other Beatles," he noted. "They thanked me for it years later."

McCartney also said he thinks that, had Lennon stayed, The Beatles "could have" survived for longer, adding, "This was my band, this was my job, this was my life, so I wanted it to continue."