Author Peter Biskind told the New York Post newspaper he had based the figure on “simple arithmetic”.

According to Biskind, Beatty slept with “12,775 women, give or take, a figure that does not include daytime quickies, drive-bys, casual gropings, stolen kisses and so on.”

Biskind said he managed to form a friendship with the Bonnie and Clyde star who eventually opened up to him on his long list of affairs with Hollywood’s leading ladies.

But the 72-year-old actor and producer has already denied the book, titled Star: How Warren Beatty Seduced America, was authorised and said it contains many false assertions.

Beatty’s attorney, Bertram Fields told the Huffington Post the book was full of purported quotes from the actor which he had never said.

According to Biskind, Beatty’s former lovers included Jane Fonda, Joan Collins, Leslie Caron, Isabelle Adjani, Julie Christie, Diane Keaton, and Madonna.

The book also contains a claim from The Nanny star Fran Drescher in which she recalls Beatty inviting her to take part in a threesome. Drescher turned down the offer.

On Beatty’s affair with Collins, Biskind wrote in the book the actor made love to the leading lady “relentlessly”.

“For Collins, it was too much of a good thing,” he wrote. “One Sunday morning, exhausted, she stumbled out of bed. Dragging on a forbidden cigarette, she said, ‘I don’t think I can last much longer. He never stops — it must be all those vitamins he takes . . . In a few years, I’ll be worn out.'”

Source: ninemsn.com.au