Katy Perry last night performed at a rally for US President Barack Obama.

The ‘Firework’ singer, who joined the likes of Bon Jovi, Jennifer Hudson and Stevie Wonder at the sold-out '30 Days To Victory' concert at Los Angeles’ Nokia Theater, later took to Twitter to explain why she chose to appear at the event:

"I sang for President @BarackObama last night because I believe in Equal Rights #ForAll #Vote." 

The fundraiser, which was attended by guest of honour Obama as well as celebrities including George Clooney, was organised to pull in last-minute donations for the President’s re-election campaign.