Osbourne slams Morgan's "appalling" behaviour

America's Got Talent judge Sharon Osbourne has criticised fellow panellist Piers Morgan for what she described as his "appalling behaviour" on the show.

It is understood that Osbourne stormed off the set of the NBC show and threatened to quit after Morgan showed what she called a "definite dislike for children or younger artists."

She told TV Guide: "It was appalling behaviour. I just couldn't take the way he was talking to them. And it was not just the children - he was being particularly appalling to everybody that day. I just had it. I was ready to scream."

The director of the show was apparently so concerned that Osbourne would not turn up for the next day's filming that executive producer Simon Cowell was called in to resolve the situaiton.

"Simon is always the voice of reason," explained Osbourne, who spoke to Cowell by phone. "He said... 'You have got to be professional... You have worked with worse people in your life. You can handle this.'"