Simon is back!
Unsurprisingly, the music mogul wasted no time in playfully insulting fellow judges Demi Lovato and Britney Spears - labelling them 'the gruesome twosome' on twitter!
Simon tweeted: "Unfortunately Britney & Demi are now known as the gruesome twosome.V happy to be back-Demi more annoying than ever, Britney has grown claws!"
Britters was quick to reply, warning Simon to play nice. "@SimonCowell And I'm not afraid to use them!" she tweeted.
Despite Simon's jibes, he and Demi actually seem to be getting on very well - just have a look at this instagram pic, tweeted by @TheXFactorUSA!
Looks like Mr Cowell is glad to be back.
We're certainly looking forward to seeing Britney, Demi, LA and Simon in action when the new series of The X Factor USA airs. Are you?
IMAGES: @TheXFactorUSA twitter