The X Factor could be set to lose two of its most popular characters, with presenter Dermot O'Leary and judge Simon Cowell both rumoured to be following the hit show over to the US next year.

O'Leary has been the presenter of the X Factor for the past 4 series, after replacing Kate Thornton in 2007.

There are also rumours about who will replace them, with comic actor James Corden being lined up to fill Dermot's shoes and talk of former Pussycat Dolls singer, Nicole Sherzinger, becoming a new judge on the TV talent show.

These are not the first rumours of X Factor stalwarts leaving the show, with persistent suggestions that Cheryl Cole will be joining the judging line up in America. It is not known if Cole will continue to fulfill her role as a judge in the UK.

An announcement is expected to be made in January to confirm the celebrities who will judge the US X Factor.