Cowell slates Beyonce, praises Ashlee

Simon Cowell doesn't buy the hype surrounding global superstar Beyonce.

The X Factor and American Idol judge said he was "mystified" by the huge success of the Destiny's Child singer.

"I find the whole Beyonce thing really mystifying," Cowell told Esquire magazine. "She's not sexy, she hasn't got a great body and she's not a great singer."

The music mogul stood up to defend Ashlee Simpson, meanwhile, who was recently caught out lip-synching on a Saturday Night Live performance.

He added: "Why should you have to do something substandard just for the sake of being real? If it sounds better with the vocal you recorded, why shouldn't people listen to that? There's almost a witch-hunt mentality about people miming."

The fourth season of Idol premiered Tuesday night to a hefty 33.5 million audience.