Simon Cowell has dismissed reports that his X Factor USA colleague Britney Spears is becoming unstable due to the demands of filming the show.

There has been speculation doing the rounds that Spears was "coming undone" as a result of filming the audition process.

However, Cowell spoke to X17 Online in praise of Spears and suggested that he was the one becoming unstable, not her. He said:

"No she's not unstable, I'm the one who's unstable! She's working out great, I mean, all these reports that we've fallen out, it's nonsense. She's doing a great job."

He added: "Do you know what? Like I said, she's been amazing. She's really taking time to learn how to do this. She's got her confidence up. Once people give her a chance, I think people are really going to get her. She's gonna be a big surprise. She's a tough judge."