Simon Cowell has threatened to sack feuding judges Sharon Osbourne and Dannii Minogue from the next series of The X Factor, according to the papers.

The Sun reports that Simon is tired of their behind-the-scenes battles, which dominated the last series – and wants the squabbles to end.

“Sharon said she doesn’t want to come back with Dannii – and Dannii said she doesn’t want to work with Sharon,” a source told the paper.

“But Simon has banged both their heads together and told them, ‘If you don’t shut up – I can replace you both’.They don’t have to be best friends – but they do have to work together.”

The paper reported last year how one fight between the pair left Dannii in tears just moments before the first of the live finals in October.

And both Sharon and Dannii made no secret of their dislike for each other – with Sharon launching into a tirade about the Aussie songstress on Graham Norton’s chat show, and Dannii calling Sharon an “old witch” on a spoof sketch during an ad break in the final.

Despite Simon’s threats, however, show bosses are keen to sign up both for another series. “Viewers were hooked on the backstage battles,” the source said. “It makes for very interesting TV.”

The show will return later in the year.