London, Sep 16 - British supermodel Kate Moss wants to sing at her good friend Simon Cowell's birthday party.

Though the 35-year-old is keen to sing, she is unsure about what to sing on Cowell's 50th birthday bash Oct 7, reports femalefirst.co.uk.

'It's a toss up between a sexy Marilyn Monroe style 'Happy Birthday' or Lily Allen's 'Not Fair', which she has been practising with her friend Lily,' said a source.

Guests expected to attend the party include music legend Sir Elton John and his partner David Furnish, Hollywood actor Kevin Spacey, actress Denise Richards, and Australian pop star Kylie Minogue.

Moss will have to ensure her singing is pitch-perfect on the night as she will be performing alongside some of the world's biggest names including Leona Lewis.

--Indo-Asian news Service

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