John Lennon’s son Julian has finally forgiven his late father for walking out on him as a child, insisting he has let go of all his "anger and bitterness."

The Beatles star, who was murdered in New York City in 1980, left his first wife Cynthia Powell for Yoko Ono and had little contact with his young son after the divorce in 1968.

Julian began to rebuild his relationship with his father in the 1970s, but never fully forgave him for abandoning his family.

But the musician, 46, admits he has finally come to terms with the music legend's role in his life, after writing a new song about his recently deceased childhood friend Lucy Vodden - who inspired Lennon's Beatles classic Lucy in the Sky with Diamonds.

Julian says, "It's come full circle for me in many respects. I had a lot of bitterness and anger. It wasn't until the writing of this song that I really forgave my father.

"I realized if I continued to feel that anger and bitterness towards my dad, I would have a cloud hanging over my head. Writing is therapy for me. It also allowed me to embrace dad and the Beatles."