British-Irish girl group The Saturdays surprised fans by inviting reggae star Sean Paul to join them onstage at their concert in New York on Thursday night (17Jan13).

The fivesome performed to a sold-out crowd at Manhattan's Highline Ballroom as part of its bid to break into the U.S. market, singing and dancing its way through tracks including Ego, 30 Days, Up and Forever is Over.

But the pop stars had an extra special treat in store for audience - they brought out Sean Paul towards the end of the show to collaborate on their new single What About Us.

Taking to after the big gig, The Saturdays wrote, "New York City!! They don't call you the city that never sleeps for nothing! You guys Rocked the HLBallrooom!! Massive thanks to duttypaul for joining us for WhatAboutUs tonight".