It’s been previously claimed that the former Spice Girl was the front-runner to join the panel, but it’s now been reported that Simon wants the star - who is already a judge on ‘America’s Got Talent’ - to prove that she is committed to the UK series.
“For Mel to get the job she has to prove she can devote enough time to the show and prove her other commitments won’t get in the way.
“She is the front-runner for the fourth judging spot but will only get it if Simon is satisfied it will work.”
Simon was reportedly impressed with the singer's 'no holds barred' approach to judging when she made a guest appearance on ‘The X Factor’ back in 2012, and is also hoping to recruit her to see if there are fireworks between Mel and Cheryl Cole, who confirmed back in March that she was returning to the show after a three-year break.
The source added: “‘The X Factor’ judging panel is all about the drama.
“And Mel is sure to rub Cheryl up the wrong way, which Simon is really looking forward to!”
It’s still not known if Louis Walsh will be returning to the panel, as although Simon Cowell has expressed his desire for him to return, it was previously reported that ‘X Factor’ bosses were putting pressure on him to drop Louis from the series.