Rihanna has revealed that she turned down the US X Factor job as she is too busy.

The singer was one of a number of musicians asked to join Simon Cowell on the American version of the X Factor.

"It's something I'd have loved to do but our schedule doesn't allow it. You have to be around for months which would've been impossible for me," Rihanna told The Sun.

Fergie and Katy Perry are also thought to be potential judges, while X Factor UK judge Cheryl Cole has also been linked to the post.

The series is due to begin later this year. Auditions for the programme have already begun.

(by Holly Frith)