Al Pacino has apologized for the singing in his latest movie Danny Collins, saying he felt terrible stage fright during filming and forgot the words to one particular song. Joking at the movie's premiere at London's Ham Yard Hotel, the Oscar-winner said: "I'm sorry about the singing, I had to do it for the part."

Al PacinoAl Pacino has apologized for the singing in his latest movie Danny Collins

"I'll tell you the one thing you learn about singing in front of an audience, is it's really hard to hold onto the words. You forget them because you're so nervous.

"I went on stage in the Greek Theatre in LA to perform with the great band Chicago. They had prepped the audience up for my going on and I came out as Danny Collins, and I'm so glad I was playing him, because if I would have come out myself I would have fainted dead away!"

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In the movie, Pacino's character abandons a life of touring to build a relationship with his family and starts to write songs again. The Godfather star used one particular run in with a legendary musician as inspiration for his performances.

"I ran into John Lennon. We were like ships in the night, we passed each other. But he looked at me and smiled, and we both waved. It was a moment that I'll never forget," he said.

Danny Collins also stars fellow Oscar-winner Christopher Plummer as Pacino's manager, as well as a glittering supporting cast including Annette Bening, Jennifer Garner and Bobb Cannavale.

Danny Collins, which features music by John Lennon, opens in UK cinemas on May 29.

Watch the trailer for Danny Collins: