Simon Cowell has warned Nick Grimshaw to cut down his partying if he wants 'The X Factor' job,

Nick Grimshaw

Nick Grimshaw

The 30-year-old Radio 1 DJ is rumoured to be signing a deal with ITV to replace Louis Walsh as a judge on the show, but the 55-year-old music mogul has made it clear that he won't tolerate excessive bad behaviour, due to the DJ turning up on his breakfast show drunk and also failing to show after a weekend in Istanbul.

A source told The Sun newspaper: "No one would expect (Nick) to be a saint, we'd want him to be himself. But obviously it's important that you turn up for work."

Grimmy hasn't denied a potential involvement in the ITV singing contest, but he insisted it is only "speculation" as nothing has been confirmed.

Speaking about the rumours, he previously said: "They're nothing but speculation which pretty much everyone's, who has had anything to do with music, names have been involved.

"So there's nothing more to that so far."

The 30-year-old star - who has previously announced his love for the programme on his radio show - admitted he would take the part if it was offered to him, but said he thinks 'Rock DJ' hitmaker Robbie Williams would also be a great judge.