Diddy says his relationship IS over - as Sienna arrives in town

Sienna Miller arrived in New York to promote her new film as close friend Sean 'Diddy' Combs confirmed his relationship with long-time girlfriend Kim Porter is over.

Arriving to appear on chat show David Letterman, Sienna's presence in the Big Apple will cause renewed speculation regarding the nature of her close friendship with Combs, which intensified after the pair were seen partying together after the Concert for Diana.

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Last week Sienna denied reports of a blossoming romance between the unlikely couple. The Factory Girl star said she and Combs are just 'good friends' but she did admit to being in love with a mystery man.

According to website Female First she said: "I am in love with someone, but not Puff Daddy. He's just a good friend. Anyway he has a beautiful girlfriend".

Sienna is in New York on a trip to promote film Stardust, co-starring Robert De Niro, Ricky Gervais, and Sir Ian McKellen, in which she plays the lead character, Victoria Forrester.

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Sienna Miller's personal life, including her very public relationship with actor Jude Law, has somewhat overshadowed her acting career.

Law had an affair with his children's nanny, and it's also rumoured that Miller had an affair with James Bond star Daniel Craig.

Combs, 37, and Porter, a former model, had been together for roughly 10 years, and in December Porter gave birth to their twin daughters, D'Lila Star and Jessie James. The pair also have a son named Christian.

Several years ago, the couple broke up when Combs was dating actress-singer Jennifer Lopez, but when that ended, he and Porter resumed their relationship.

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