Lily Allen was joined onstage by a host of celebrity friends during Coldplay's charity gig on Thursday (19Dec13).

The Smile singer was one of the performers drafted in to play at the band's third Under 1 Roof concert at the Eventim Apollo in London, in support of the Kids Company charity.

The pop star treated fans to duets with Robbie Williams and Coldplay's Chris Martin, and thrilled the audience when Keane's Tim Rice-Oxley joined her to perform her Christmas cover of the band's hit Somewhere Only We Know.

Other performances at the event, which was hosted by Fearne Cotton, came from Coldplay themselves, hip-hop duo Rizzle Kicks, magician Dynamo, and Ricky Gervais' The Office character David Brent with his band Foregone Conclusion.