Katy Perry Rocks American Flag Dress For 2013 Kids' Inaugural Concert – Video

The 'I Kissed A Girl' singer hit the stage for the special event honouring the families of those in the military.

Katy Perry and Usher were among the star performers at this weekend's special Kids' Inaugural concert in Washington as Barack Obama prepares for his second term as US President.

The 'Hot N Cold' singer wore an American flag dress for the event, which was hosted by First Lady Michelle Obama, and performed some of her biggest hit singles.

The singer took to the stage after the likes of Usher, Far East Movement and Mindless Behaviour and gave live renditions of such tracks as 'Teenage Dream', 'Firework' and 'Part Of Me'.

R&B star Usher wore his trademark red boots as he got those inside the Convention Center dancing with a string of his most uplifting tracks.

There were also video messages played throughout the show, featuring such celebrities as Jimmy Fallon, Ellen DeGeneres and The Wanted.

Members of the Glee cast also performed with Amber Riley giving a rousing rendition of Christina Aguilera's 'Beautiful'. 

Obama and Vice President Joe Biden also appeared at the end of the show as they praised the efforts of those in the Military and the support of their families.

Today (21st January), will also see a special concert in Capitol Hill in Washington as Obama is sworn in for his new term.

Performers will include Beyonce, Kelly Clarkson and James Taylor. 

Meanwhile, Lady Gaga is rumoured to be headlining the Inaugural Ball tomorrow evening.

Watch a video of Katy Perry performing her hit song 'Firework' in Washington this weekend below: