Usher

Usher

"This is important for the youth to realise how powerful they are and to stay active and stay informed, and go out when it's time to vote."

U.S. President Barack Obama's had help from a whole clutch of stars to celebrate his official inauguration in Washington D.C. this Monday.

The likes of Will.I.Am, John Legend, Katy Perry and Usher were among the faces coming down to the capital, with the Black Eyed Peas star even performing with with fellow rapers Common, T-Pain and singer Legend in honour of the next generation of American voters.

Will.I.Am told reporters that "This is important for the youth to realise how powerful they are and to stay active and stay informed, and go out when it's time to vote. And not just for a presidential candidate, but for local government, too".

Kelly Clarkson, Beyonce, Stevie Wonder, Alicia Keys, fun. and Cyndi Lauper are all gearing up to perform at events related to Obama's inauguration, while Lady Gaga will reportedly sing at a private ball for the president's campaign staff on Tuesday.