Musicians Natalia Kills and Willy Moon were removed from the judging panel last month (Mar15) for ridiculing contestant Joe Irvine during a live broadcast, with Kills calling him "disgusting" and a "laughing stock" and her husband Moon comparing him to movie psychopath Norman Bates.

The X Factor creator Cowell has now spoken out on the scandal, admitting he likes judges to be tough but they went too far, and they sealed their fate by refusing to apologise for their behaviour.

He tells Britain's Weekend magazine, "It was hateful... She sounded mad. It didn't even make sense... Where they cocked (messed) up was that they didn't apologise straight away. If they'd both been genuinely sorry and called me, and apologised to the guy and his family, who knows what could have happened? They didn't. They were quite defensive. Their attitude was, 'So what? That's what we're like'. It was the arrogance of it that did for them.

"It is sometimes a fine line, but there's a definite line and they crossed it. I don't think anyone's ever gone as far as that on any show we've ever made."

Kills and Moon have since apologised to Irvine. They were replaced by Australian actress/singer Natalie Bassingthwaighte and British drummer Shelton Woolright.