Simon Cowell has spoken out about his X Factor USA colleague Britney Spears.

Spears joined the judging panel along with Demi Lovato earlier this year, finalising the line-up after Cowell and L.A. Reid had already confirmed their roles.

Speaking at an X Factor USA press conference in Miami, Cowell said that Spears is actually a "quite mean" judge, despite her pop princess roots. He said:

"Britney is quite mean, which I think you will discover."

Cowell added that both Spears and Lovato are not afraid to voice their opinions and are more than happy to say no to people. He said:

"They are harder to please than me or L.A. They are very happy giving people a 'no'. They definitely have their own opinions."