Simon Cowell is mentoring the over 25s in the new series of The X Factor

Simon Cowell held a lavish do on Saturday night to celebrate his 50th birthday.

Guests at the bash included Gordon Ramsay, 42, Kate Moss, 35, Jordan, 31, Terri Seymour, 34, Sinitta, 40, and Amanda Holden, 38.

Simon's fellow X Factor judges Dannii Minogue, 37, Cheryl Cole, 26, and Louis Walsh, 57, were also at the party.

As his celebrity pals headed up the driveway of an 18th century mansion in Hertfordshire, they were greeted with a giant image of Simon beamed on to the walls. 

Simon's brother Nicholas, 48, led a toast to the pop mogul and his mum Julie, 82, was said to have been left open-mouthed by the racy entertainment.

A cabaret act apparently took to the stage dressed as a vagina and started playing with sex toys.

‘It was a brilliant party, some parts of it had an outrageously camp theme,' publicist Max Clifford, 66, tells the Daily Star.

‘The funniest thing was seeing Simon trying to explain it to his mum, who was there with a priest and some of her friends from church.

‘She asked what it was and he told her it was a sideways mouth and a toothbrush but it was very suggestive and it was very clear what it was supposed to be.'

SEE PICTURES All the stars at Simon Cowell's 50th birthday party>> 

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