Simon Cowell would "100 per cent" sign Britney Spears to US 'X Factor'.

The 'Toxic' singer has reportedly been approached to take on a judging role on the pop star search show for a reported $15 million per year and although Simon refused to confirm if she has been approached, he admitted she would be his top choice for the job.

Simon told Kiis FM's Ryan Seacrest: "If it was my decision [to sign Britney, I'd do it] 100 per cent -- if we could get her.

"We'll find out very soon ... if we've spoke to her.

"There are a lot of names that have been bandied around. We've got to keep quiet about it ... we're very, very, close -- I think were very close."

One of the sticking points in negotiations between Britney and Simon has previously been cited as the number of series she would have to commit to.

A source has said: "Money is not an issue for the show. As of now, they are looking to pay her $12-15 million for the first season, with a drastic price hike for a second year based on ratings performance.

"Simon Cowell wants at least a two-year commitment and Britney wants an out clause if she doesn't want to continue after one year of service."

Simon has been particularly complimentary about the star in recent weeks, praising Britney - who has sons Sean Preston, six, and Jayden James, five, with ex-husband Kevin Federline - for her "resilience" in juggling her music and family life.

He said: "I'm fascinated by her. The fact that she's one of the most talked about - not just pop stars - but people in the world today, means that you've got this star power.

"This girl has got resilience. I would think that if she's managed to sustain a family, a career, which is tough, ['X Factor' would be] a walk in the park."