Sir Paul McCartney and Yoko Ono are both said to be furious about a book which makes controversial claims about John Lennon.
Sir Paul and Ono, Lennon's widow, are both understood to have contributed to the biography, which claims Lennon wanted a gay relationship with Sir Paul.
John Lennon: The Life also suggests that Lennon fantasised about having a sexual relationship with his mother.
The biography has been written by the Beatles author Philip Norman.
“Both Sir Paul and Yoko are extremely angry and upset,” a source told the Sun newspaper.
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