12/01/2008 AT 12:20 PM EST
If Simon Cowell
gets his way, Britney Spears
could be the next guest star on American Idol
The British producer raved about the singer after she performed on
his British talent show X Factor
"Of all the artists I have ever had on any of these shows, there was more buzz, more excitement for this girl [than anyone else]," Cowell told Ryan Seacrest
on his KIIS-FM radio show
. "It was as if the president was on the show. I love it. I think if you're going to be a star, be a star."
Cowell, who is a fan of Spears's single "Womanizer", said it would be crazy to not invite her to be on Idol
when it returns in January. "I would literally have her on my show every week for the next 10 years," he said.
Spears performed "Womanizer" before listening to the show's five remaining contestants sing her songs. Behind the scenes, Cowell said the superstar was a bit shy. "To be fair, and this may be a bit egotistical, I think she was in awe of me," he said. "She was just staring at me. I said, 'Touch me, I'm human,' and I think that broke the ice."
Cowell also opened up about his recent split
with longtime girlfriend Terri Seymour. "I take it day by day, that's the only thing you can do," Cowell said. "You just get through the day. I've given myself years on this one. I'm not saying it's easy, but it's a day-by-day struggle."
2005: Simon's feud with Paul heats up on Idol
2000: Britney burns up the charts with 'Baby One More Time'