TV host's upset about being fired from The X Factor
She was replaced by Dermot O’Leary, 35, as host of the ITV show in 2007.
Kate, 35, who has 21-month-old son Ben with DJ fiancé Darren Emerson, 37, reckons the move was a publicity stunt.
‘I’ll never talk to Simon again,’ she says. ‘He fired me to create headlines without even telling me beforehand, when we had been good friends.
‘I wouldn’t watch the show now because it would be like seeing your ex-boyfriend with his new girlfriend.’
Pet Shop Boys frontman Neil Tennant, 54, has also hit out at Simon, 49.
‘What bugs me is that his idea of pop music is so narrow,’ he tells the Radio Times.
‘It’s basically people singing Whitney Houston, Mariah Carey, maybe Elton John.
‘And if it’s not power ballads it’s an equally narrow version of disco.’