Britney Spears and Demi Lovato to judge X Factor USA

Britney Spears and Demi Lovato have signed up as judges for the US version of the X Factor.

The singers will join Simon Cowell and L.A. Reid on the judging panel when the show returns in the autumn.
Fox confirmed earlier this year that Paula Abdul and Nicole Scherzinger would not be returning.
The programme's creator Simon Cowell had promised to shake up the show after ratings failed to match his predictions.
Speaking as the new judges were presented in New York, he said: "We're going to make this the best series we've ever made.
"We started off well last year but we are going to seriously kick butt with the addition of these guys."