Demi Lovato is reportedly close to signing a contract for 'The X Factor'.

Demi Lovato

Demi Lovato

The 22-year-old star - who was a judge on the US version of the show for two years from 2012 - is said to have agreed to join the UK version after it was claimed Simon Cowell has sacked Mel B after just one series.

A source told Daily Mirror newspaper: "Simon's management phoned to see when Demi could sign her contract about a week ago.

"They both have busy schedules but she is planning to do it as soon as possible and Simon is eager to get the judging panel sorted."

The 'Heart Attack' singer is currently on her self-titled world tour but her last concert date is scheduled for June 6, while auditions for the show set to kick off later this month.

Simon, 55, previously hinted only he and Cheryl Fernandez-Versini from last year's line up would be returning to the show while Louis Walsh has claimed his time is up.

He said previously: "I think I'm done with 'X Factor' honestly. My day job is as a manager, I've kind of neglected that. I want to get back to being a manager."

Meanwhile, if Demi does end up joining the show, new host Olly Murs - who, along with Caroline Flack, is replacing Dermot O'Leary - will be happy as the pair performed their duet 'Up' during the final last year and are said to be close friends.