Khloe Kardashian and Mario Lopez are set to host The X Factor. The pop star search show started last week, but still lacks a presenter to front its live episodes, but sources say reality TV star Khloe and former Saved by the Bell actor are the poised to sign on as presenters.

Mario - who appeared in the third season of Dancing with the Stars in 2006 - was tipped to host the first series of the show last year, but the job went to Steve Jones, who was dropped after unsatisfactory ratings. Show boss Simon Cowell has previously hinted Khloe, 28, was his first choice to host the show. "I know whom I would like, but now I have to get it approved by the network. We have screen-tested a load of people ... It could be a Kardashian. I think that would work. I'm a fan of putting inexperienced hosts on this show. We have to find people who have a great chemistry, but Khloe is definitely up there in the running," he said earlier this year.

Despite Simon's claims, Mario, 38, has hosting experience, fronting America's Best Dance Crew on MTV.

If negotiations with either potential host fall through, High School Musical actor Corbin Bleu is said to be ready to step up to the mark. The main stumbling block would be if the E! Network - who Khloe has an exclusive contract with - refuses to give permission for her to appear on the show, aired on the Fox network.