Simon Cowell has revealed that Cheryl Cole completely changed when she started working with him on US X Factor.

Without crowds of fans greeting her everywhere, Cheryl didn’t know quite how to act. 

‘I was seeing a different person,’ says Simon, 51.

She was like Princess Diana when she would walk out in England.

I accepted the fact that people didn’t know her [in US], but I think it did have an effect on her.

I said: “Cheryl, you’ve got to raise your game a bit. This is America, it’s a much tougher market.”‘

After she was dumped from the judging panel, Cheryl, 28, was offered the chance to return to the UK version of the show – with a huge pay rise – but didn’t get back to Simon about his offer.

I never heard from her,’ Simon tells the Hollywood Reporter.

I think her silence was quite damning.

I stand by the decisions I’ve made, and I knew the implications when I did it publicly – that I was going to get slaughtered, and I did.’

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Anna Francis