Mariah Carey wants to be `judge of judges` in Simon Cowell`s X Factor

The superstar singer, who gave birth to twins Monroe and Moroccan Scott in April, was already rumoured to be joining the US edition of the hit talent show as a mentor for an episode or two.

But now Cowell has confirmed that she is in talks for a more major role - even telling Cowell she wants to be 'the judge of the judges'.

'I think Mariah will have a role on the TV live shows. I met her recently and she was on great form,' Cowell said.

'And her idea was to be the judge of the judges, which only Mariah could come up with.'

A source told Entertainment Weekly: 'Mariah and Simon are great friends, and now she has had her babies, it's very possible that she will be involved some way in the show.

'She has always said she wanted to work with the show, so it's something they will certainly be discussing ideas for soon.'

The US version of The X Factor premieres on September 21.

Cowell will appear on the show along with judges Nicole Scherzinger, LA Reid and Paula Abdul.