Robert Downey Jr. and Katy Perry are set to present prizes at the Nickelodeon Kids' Choice Awards on Saturday (27.03.10).

The famous pair are among a host of stars, including Tina Fey, Steve Carell, Chris Rock, Jackie Chan, Jonah Hill, Queen Latifah, David Spade and Dev Patel, who will give out prizes at this weekend's ceremony in Los Angeles.

The event - which is being hosted by 'Mall Cop' actor Kevin James - will also feature performances from 'Rudeboy' singer Rihanna and teen sensation Justin Bieber, while eight-time Olympic speed skating medallist Apolo Anton Ohno will attempt to set a new world record for being catapulted into the show's green slime via the Kids' Choice Awards Slime Slingshot.

Voting in 19 categories for the 23rd Annual Kids' Choice Awards - which take place at UCLA's Pauley Pavilion - is still open.

'Hannah Montana' star Miley Cyrus has the most nominations after receiving nods for Favourite Singer, Favourite TV Actress and Favourite Movie Actress, as well as Favourite Song for her track 'Party in the USA'.

In both music categories she faces competition from Lady GaGa - whose single 'Paparazzi' made the Favourite Song list - and Taylor Swift, whose track 'You Belong with Me' is competing for the Favourite Song title.

Black Eyed Peas are also up for two awards, Favourite Single for 'I Gotta Feeling' and Favourite Group.