Katy Perry proved she has a sense of humour at the Kids Choice Awards in LA, donning a blue wig and a plastic dress to get gunged in front of a celebrity-packed audience.

The annual Nickelodeon event is a chance for children to honour their favourite movies, music stars and books, as well as seeing some usually glamorous celebrities covered in slime.

Miley Cyrus collected the Favourite Actress prize for Hannah Montana: The Movie, while Taylor Lautner saw off his Twilight co-star Robert Pattinson so win Favourite Actor.

Michelle Obama was honoured with the 'Big Help' award which she picked up via salletite. The First Lady used the opportunity to encourage children to be healthy.

"You guys have to make smart and healthy choices in your own lives that will give you the focus to do better in school and the energy to play all day long," she said.

Tina Fey and Steve Carell left covered in green gunge after they picked up the Slimetime Achievement Award.