Joined by Kelly Clarkson, the first American Idol winner, the British television and music mogul basked in the limelight as he recalled his time as a reality show judge, record producer and creator of long-running franchises The X Factor, America's Got Talent and Britain's Got Talent.

"It's been a blast the last 18 years," said the 58-year-old Cowell. "If anyone says fame is a bad thing, I don't know what you're talking about. It's the best thing in the world."

Cowell became a household name as a judge on American Idol from 2001-2010 thanks to his harsh critiques of aspiring singers, often prefaced with the line "I don't mean to be rude but...".

He went on to launch The X Factor in Britain and the United States, and the British and U.S versions of Got Talent, as well as signing boy band One Direction and girl band Fifth Harmony to his Syco record label.

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Clarkson said Cowell had a talent for spotting authentic people with raw talent and developing them.

"He appreciates you being yourself, and that's very rare. In this industry I think people just want you to fit in to something," the Grammy-winning singer said.

Cowell was joined at the unveiling by British X Factor winner Leona Lewis, One Direction's Louis Tomlinson and America's Got Talent judges Heidi Klum, Howie Mandel and Mel B.

"Thank you, all of you, for turning up and making this happen. It means an awful lot to me," he said.