KATY PERRY has been signed up as a guest judge on the new series of American Idol.
Following resident judge Paula Abdul's departure from the show after eight series this week, Perry will take her place for one of the audition shows.
The news comes the day after it was revealed that former Spice Girl Victoria Beckham will also appear as a guest judge on the US version of Britain's The X Factor.
But executives at Fox, which broadcasts the show said they are searching for a permanent, fourth judge to sit in Abdul's seat when the ninth season of the show returns to TV in early 2010.