X Factor: Dappy tells Simon Cowell to "watch his back"

N-Dubz rapper Dappy has told X Factor supremo Simon Cowell to "watch his back" after he and bandmate Fazer were banned from the show.

New judge Tulisa asked Cowell for her fellow N-Dubz members to be guest mentors at the judges' houses stage, but the boss said no, the Daily Mirror reports.

Dappy said the pair would have loved to go on the show but executives must have thought they were too much of a gamble.

"Gary Barlow chose Robbie Williams and he got Robbie Williams. Tulisa wanted me and Fazer but didn't get me and Fazer. It's a joke. Instead Tulisa's been given Jessie J. That's cool too. Jessie is amazing, she's great, and we love that. But still the whole thing is wrong. I'm devastated they don't think we're capable of going on there and helping her.

"I'm coming for you, bro. Watch your back, Simon," he added.

The 24-year-old, who is currently promoting his new single No Regrets, went on to say he would show Cowell he was wrong by having hit singles and number ones.