Simon Cowell allegedly had affair with Dannii Minogue

X Factor judge Simon Cowell allegedly had a romance with fellow judge Dannii Minogue, says a new biography.

A book entitled "The Intimate Life Of Simon Cowell", by former BBC journalist Tom Bower quotes Cowell as saying he was genuinely in love with her. He said: "I had a crush on her. It was Dannii's hair, the sexy clothes... I was like a schoolboy. She was foxy. She was a real man's girl."

The book states that Cowell targeted Minogue by adding her as a judge on X Factor in 2007. Minogue later denied reports that the two were an item after paparazzi snapped a photo of them in a car, allegedly holding hands.

Minogue brushed off reports, claiming that the angle of the photo made it appear that they were intimate, but that no one believed her.

Earlier this month, Minogue announced her split from partner Kris Smith, a former British rugby league player and father of her baby son.

Minogue and Cowell still work together on TV programme "Australia's Got Talent".

Cowell responded to the biography's claims via Twitter with a tongue-in-cheek comment: "Just seen the TV ad for the unauthorised book on me. Yikes!"

Cowell's most recent relationship ended in January 2011.

Media reports said that Cowell regretted his engagement to make-up artist Mezhgan Hussainy.

The pair were engaged on Valentine's Day in 2010 but split up last year after a series of heated arguments.

Cowell reportedly told friends he was attracted to "crazy women" with volatile personalities.

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