Cheryl Fernandez-Versini and Louis Walsh are allegedly 'at war' and their relationship has 'turned toxic'.

READ: X FACTOR JUDGE'S CATEGORIES REVEALED – AND SIMON ISN'T HAPPY

According to sources, Louis, 61, never wanted 31-year-old Cheryl to return to the panel but now she has, he's constantly making digs at her.

Now recently married Cheryl is refusing to be in the same room as the music manager, unless she absolutely has to.

An X Factor insider told The Sun: "The atmosphere is toxic – she hates him with a real passion and it shows."

READ: CHERYL FERNANDEZ-VERSINI WARNS X FACTOR CONTESTANTS 'NOT TO CHEAT ON THEIR PARTNERS'

Apparently Cheryl didn't want Louis to return this year either, which is making the problem worse.

The source continued: "It's no secret that Cheryl didn't want Louis back on the panel, but since then he has been lording his victory and takes every opportunity to knock her.

"On the panel he has repeatedly slapped her down, and she has given him some poisonous stares in return. If looks could kill, Louis would be a dead man."

Louis is said to think that Cheryl is 'unfit' to judge the talent on the show, and their feud is making the war between Sharon Osbourne and Dannii Minogue look like a harmless tiff.

READ: IS TULISA HEADING FOR X FACTOR RETURN?

In contrast, Cheryl and new judge Mel B, 39, are apparently getting on great.

We can’t help but think head judge Simon Cowell, 54, is loving all of the drama between judges.