Various media sources are today reporting that former Take That member Robbie Williams and No Doubt front lady Gwen Stefani are being lined up for guest judging slots on the UK X Factor.

UK taboid The Sun are reporting that show bosses have approached the pair in a bid to boost show ratings. With auditions starting in Liverpool this week time is running out for X Factor big wigs to find a permanent replacement for the recently departed Kelly Rowland. Danni Minogue allegedly turned down a £1 million offer to return to the show recently and bosses fear the previous lure and media attention of the show is now starting to fade.

The Sun also reports that Rod Stewart and Alicia Keys will join Williams and Stefani as guest judges, a show insider revealed more details saying, “At this rate the fourth judge may not be signed until much later in the series, Dannii turning them down was a massive blow because as far as ITV1 and The X Factor were concerned it was a done deal. The back-up plan is to have a host of guest performers take part in the regional auditions and possible Boot Camp before revealing a permanent name at the Judges’ Houses in August. Everyone involved knows how important the judges are to the success of the show. Numerous high-profile singers have come forward wanting the job. But bosses fear they aren’t big enough names to wow viewers. So it’s now panic stations to make sure they can sign up a big enough name in time.”

Other names in the frame include former Spice Girl’s Geri Halliwell and Mel B, The Saturday’s singers Frankie Sandford and Rochelle Wiseman and current Britains Got Talent judge Aleesha Dixon.