Published Thursday, 29 October 2009
The twins who have built up a huge following on the back of their chaotic performances, have yet to face the judges' vote - much to Cowell's annoyance.
On Thursday he said it would be a "disaster" if the 18-year-old Irish duo - dubbed Jedward by their legion of fans - win.
Speaking at a press conference to announce his patronage of the Children's Hospices UK charity, he said it was impossible to predict the winner of this year's competition - but that he knew who he did not want to win.
"I'm just praying it's not John and Edward," he said.
"But there's a chance, according to reports this week, that they will.
"To be fair, we put them in a competition where it's a public vote, and we have to live, unfortunately, with the public vote.
"If they win, it will be a complete and utter disaster.
I'd probably sulk for about six months, and I'd probably get on a very fast plane out of the country."
He said Louis Walsh would be "in trouble" if the pair were to triumph.
"The fact is, it's a singing competition, and they can't sing," he added. "I don't dislike them as people. I just don't think they are the act we were looking for."
He also revealed that he has been disappointed with popular contestant Essex girl Stacey Solomon - likening her to a candle.
Cowell said Danyl Johnson, in his own category, puts on a good show, unlike the single mother.
"She's like a singing candle," said Cowell. "She hasn't moved in three weeks. I'd rather see Danyl than that any day."
He has told his contestants to "raise their game" after favourite Danyl nearly got voted off the show last week.
Cowell, mentoring the over-25s category in this year's show, said: "We have got to make them better. We have got to prove the point that it's a singing competition.
"Particularly Danyl, because he was in the bottom two, and he's back on Saturday to prove he should be there."
He revealed a meeting was called last Sunday night after the second live show of the weekend, but denied it was a "crisis meeting".
He said: "It was simply to say I thought that Saturday's show song choices and performances weren't as good as I would have expected and that we have got to dig a bit deeper.
"We've got a responsibility while they're in the show to make them as good as possible."
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