In true British festival style, the rain poured down during the first day of the O2 Wireless Festival in London's Hyde Park yesterday, but the sun came out and so did the stars, as Jay-Z, Mark Ronson and Lily Allen all took to the stage. Lily performed a Kaiser Chiefs song with Mark, accessorising her leopard-print leggings with a cigarette, while Jay-Z reportedly mocked George W. Bush and endorsed Barack Obama during his set. A host of celebs watched from the crowd too, including Leona Lewis and Girls Aloud bandmates Nicola Roberts and Sarah Harding. Rio Ferdinand and Jodie Harsh were also spotted together — interesting pair! The festival continues until Sunday, with Morrissey, Fatboy Slim and Counting Crows all due to perform.

To see loads more pictures from the festival, including Boris Becker, David Jordan, Roisin Murphy, Ian Brown, Rio Ferdinand and Jodie Harsh, just read more

Images include: Lily Allen, Jay-Z, Mark Ronson, David Jordan, Roisin Murphy, Sarah Harding, Nicola Roberts, Leona Lewis, Rio Ferdinand, Jodie Harsh, Ian Brown, Boris Becker, Charli Morgan, Amy Watts

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