Simon Cowell is "plotting pranks" with Nick Grimshaw.

Simon Cowell

Simon Cowell

The 55-year-old music mogul is already planning to play tricks on the two girls on 'The X Factor' judging panel - Cheryl Fernandez-Versini and Rita Ora - with his fellow judge, Simon's long-time friend Sinitta has revealed.

She told the Daily Star newspaper: "I've overheard Simon plotting pranks with Grimmers already.

"They will be up to their old tricks again. Poor Cheryl and Rita."

However, filming for this year's series - which was due to start today (06.07.15) - has seen a setback after Simon's mother Julie Brett, 89, passed away.

Today's auditions in Manchester have been cancelled following Julie's tragic death after a lengthy health battle.

Speaking last night (05.07.15), a spokesperson for Syco Entertainment said: "They were due to start tomorrow and carry on into Tuesday and Wednesday.

"Tomorrow's have been cancelled and we have not made any decisions beyond that."

The tragic news has also upset all those connected to the ITV talent show.

A source shared: "Everyone at 'X Factor' is devastated for Simon and there was no suggestion that filming would go ahead."