Simon Cowell serenaded by stars

Jul 27, 2009, 9:22 GMT

Simon Cowell -The music guru was joined at the party by \'American Idol\' make-up artist Mezhgan Hussainy, who had flown from the US for the party. © Janet Mayer / PR Photos

Simon Cowell's guests sang 'You're So Vain' to him at his surprise 50th birthday party.

The music mogul was treated to a performance from Dannii Minogue, Amanda Holden and his ex-girlfriend Jackie St Claire on Saturday night (25.07.09) - before Carly Simon joked he was the inspiration behind her hit 1972 record.

During the white-themed evening at Jackie's West London home, Piers Morgan phoned Carly and put her on loud-speaker so she could talk to the guests.

She said: "I was re-recording 'You're So Vain' in the studio the other week and I was at the piano. I just thought, 'Of course, this song is all about Simon Cowell.' "

In response, Simon - who turns 50 on October 7 - quipped: "Uh, Carly, I think you're forgetting something - didn't you write 'Nobody Does It Better' about me too?"

'Strictly Come Dancing' judge Bruno Tonioli and Simon's fellow 'X Factor' judge Louis Walsh donned huge masks of the music mogul and provided the backing vocals to the surprise performance.

Simon believed the party was to celebrate Jackie's birthday and turned up with an unusual present for his former girlfriend - a giant portrait of himself.

Following the bash, Simon said: "It was supposed to be a quiet affair, so it was all a big surprise. Carly Simon did say that she wrote 'You're So Vain' about me, which was highly amusing. It was a great night."

The music guru was joined at the party by 'American Idol' make-up artist Mezhgan Hussainy, who had flown from the US for the party.

The 36-year-old beauty and the reality show judge have been spotted together several times recently.

However, Simon's spokesman has insisted the pair are "just good friends" and their relationship is "purely platonic".