Simon Cowell "genuinely thought" Cheryl Cole would accept his offer to return to the US 'X Factor'.

The 27-year-old singer was reportedly sacked from the show after just four auditions nearly two weeks ago and although she was asked to return on Saturday (04.06.11), Cheryl - who Simon said was difficult to get in touch with during the incident - refused and was officially replaced by Nicole Scherzinger earlier yesterday (06.06.11).

Speaking to reporter, he said: "We got to the point on Saturday when we genuinely thought she was going to accept the offer.

Again neither she (Cheryl) nor they (will.i.am and her management) returned any calls."

However, Simon - who claims he "did the right thing" - apologised to Cheryl and revealed he hopes they can work together again in the future.

He added: "I apologise that all this has become public and I understand the stress she is under."

A statement from Fox, Fremantlemedia North America and Syco TV earlier today revealed Nicole will join Simon, Paula Abdul and L.A. Reid on the judging panel of the show.

It read: "Nicole Scherzinger will be replacing Cheryl Cole on the judging panel of 'The X Factor'.

"Nicole will join Simon Cowell, L.A. Reid and Paula Abdul on their search across America to find the next global superstar or group to win the life-changing $5 million dollar recording deal.

"Nicole has previously joined Simon Cowell as a guest judge on 'The X Factor' for the UK version of the show in 2010. Steve Jones will act as sole host of 'The X Factor'."