Robbie Williams, Gwen Stefani for The X Factor?

Alicia Keys, Tinie Tempah also rumoured to be a judge on the show

Robbie Williams, Gwen Stefani and Alicia Keys are being touted to join the judging panel on the new series of The X Factor.

With the auditions kicking off in Liverpool this coming Wednesday (May 23), producers are frantically trying to tie down a replacement for Kelly Rowland who quit the show citing “scheduling issues” and “global commitments”.

According to the The Sun, Williams, Stefani, Keys and Tempah will appear as guest judges. The paper also reports that sources claim a full-time replacement for Rowland won’t be agreed until the boot camp stage of the show.

Williams, who appeared on the TV programme last year when he helped his Take That band mate and X Factor judge Gary Barlow pick his final acts, is rumoured to be taking up the role during the London auditions.

Yesterday, it was reported that producers had lined up wrinkly-rocker Rod Stewart to appear as a stand-in judge.

A source told the Daily Mirror that Simon Cowell had persuaded the singer to sit on the panel for the early auditions, adding that he could possibly judge during the Glasgow tapings.

Last year’s series of The X Factor was widely considered a ratings flop after steadily losing viewers in the opening weeks of its run. The show’s winners Little Mix scored a UK Number One with their cover of Damien Rice’s ‘Cannonball’, which was the fastest selling single of 2011, while also being the lowest-selling winner’s single since 2004.