The 46-year-old journalist - who now fronts CNN's 'Piers Morgan Tonight' - says he hates Kate, 38, and the supermodel despises him in equal measure.
He said: ''She doesn't like me, I don't like her.
''Kate Moss is utterly horrific. If people actually knew what she was like they would never, ever be interested in her again.
''She's just a real, spoilt little madam from Croydon. There's nothing wrong with Croydon - I was brought up near Croydon. But she's just a vile little creature.''
Moving on to the topic of Madonna, Piers - who has banned the 'Hung Up' singer from his chat show - took aim at her toned physique.
He told the Daily Mirror newspaper: ''Those arms are just terrifying. It's like watching Conan the Barbarian. She's looking even more barbaric than ever at the moment, utterly grotesque.
''When I got the CNN job I banned her from the show, permanently. She responded by saying she'd never heard of me, but we both know she's lying.''
He said: ''Gwyneth is a dark horse, much more fun than you might think.
''When I asked her about her reputation, she told me she was a demure, lovely, sweet, innocent little lady ... except In The Bedroom.
''I had a good laugh with Cameron at Vanity Fair [Oscars party]. She's a really cool girl, good fun. She wants to come on my show, but only when she's got something intelligent to say.''