Britney 'quits X Factor USA'

Britney Spears has reportedly quit 'The X Factor' USA.

The 'I'm a Slave 4 U' singer - who acted as a judge on the second series of the FOX reality TV show alongside Simon Cowell, Demi Lovato and L.A. Reid - has apparently decided not to return to the next season of the singing contest because she wants to concentrate on her own music career.