Simon Cowell proud of Leona

Simon Cowell is more proud of Leona Lewis than anyone else from his TV shows.

The 'Bleeding Love' hitmaker has found worldwide fame since winning UK programme 'The X Factor' in 2006 and the music mogul is delighted by the way the singer transformed her personality as the competition progressed.

Asked who he is most proud of, Simon said: "I would say Leona Lewis. When I first met her, she auditioned on the 'X Factor'. She was very shy and didn't believe in herself and then turned into this fantastic artist by the end. So I guess Leona, because she's the reason why we do these shows."

Simon - who is preparing to launch 'The X Factor' in the US - believes 17-year-old singing sensation Justin Bieber is one of the biggest examples of the type of star quality he and his fellow judges will be looking for in the competition.

Explaining to We Got You Covered blog on Buzznet what having X factor means, he said: " It was something we've always used for years in the music business, which is - it's very difficult to write down in words what makes somebody special. But when they walk in the room it could be presence, it could be their voice, it could be the effect they have on other people.

"I guess Justin Bieber's a good example of someone who has the 'X factor.' But you recognise it when you meet him or you see him perform, and like I said, he has that incredible effect on his fans - and that means he has it. And I've seen other people his age look almost identical to him who haven't got it. It comes from within I think."