John Lennon's half-sister Julia Baird has slammed author Philip Norman for controversially claiming the late Beatle harbored sexual feelings for their mother.

Norman alleges he has a series of audio recordings of the singer discussing his mom Julia Lennon in lurid detail - which he documents in new biography, John Lennon: The Life.

A voice purporting to be Lennon's from a 1979 interview says: "I was just remembering the time I had my hand on my mother's t-- in number one Bloomfield Road (in Liverpool). We were lying on the bed, and I was thinking, 'I wonder if I should do anything else...'

"I always think that I should have done it - presuming she would have allowed it."

But Lennon's sibling Baird has blasted the book's allegations.

She says, "John is no longer around to defend himself from some of the bizarre, sordid and downright scurrilous rumors that sadly surround his extraordinary life. It makes me so sad, especially in recent weeks, when all manner of accusations have been flying about."

Norman interviewed Lennon's widow Yoko Ono and his former Beatles bandmate Paul McCartney for the biography, but they have both since distanced themselves from the book.

(This news article provided by World Entertainment News Network)