For the first time, Sean Ono Lennon has interviewed Sir Paul McCartney about his relationship with his father, John.

“I look back on it now like a fan,” says Sir Paul of meeting Lennon.

“How lucky was I to meet this strange Teddy Boy off the bus, who played music like I did and we get together and boy, we complemented each other!”

The discussion will be part of a special two-part Radio 2 programme, John Lennon at 80, marking what would have been the late Beatle’s birthday.

During the chat, Sir Paul also plays one of the first ever Lennon-McCartney songs, Just Fun.

Written as the teenagers played truant from school, it has never been officially recorded – although a snippet was previously heard in the Beatles’ Let It Be movie.

Speaking to Sean, Sir Paul admitted his first attempts at writing with John “weren’t very good”.

“Eventually, we started to write slightly better songs and then enjoyed the process of learning together so much that it really took off.”

The documentary will also feature interviews with Sean’s half-brother, Julian, and his godfather Sir Elton John.

Radio 2 boss Helen Thomas said: “John Lennon is one of the Radio 2 audience’s most popular and best-loved musicians, so we’re thrilled and honoured that Sean’s first ever radio programme in which he talks at length about his father, alongside his brother Julian, Paul McCartney and Elton John, will be broadcast on our network.”

The programmes will be available on 3 and 4 October, ahead of Lennon’s birthday on 9 October.

The star was shot dead outside his New York apartment in 1980. Earlier this week, it emerged that his killer, Mark Chapman, had apologised to Lennon’s widow, Yoko Ono, at a parole hearing in August.

“I just want to reiterate that I’m sorry for my crime,” Chapman told the parole board at the Wende Correctional Facility in New York.

“It was an extremely selfish act. I’m sorry for the pain that I caused to her [Ono]. I think about it all of the time.”

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