Bono, Mariah Carey, Brad Pitt, Reese Witherspoon and Annie Lennox have all confirmed that they will do their bit for charity with Idol Gives Back.

Other celebrities who have signed onto the cause include Robin Williams, Celine Dion, Forest Whitaker, Billy Crystal, Kiefer Sutherland, Miley Cyrus and Fergie.

John Legend, Maroon 5, Gloria Estefan, Snoop Dogg, Boyz II Men and High Musical stars Vanessa Hudgens and Ashley Tisdale will also feature.

The star-studded charity event, which airs on US screens on April 9, aims to raise awareness and funds for six charities.

"Everyone knows it's better to give than to receive," said Ellen DeGeneres in a statement, who will be hosting the show with American Idol's Ryan Seacrest.

"Give yourself a treat and watch Idol Gives Back. You get the joy of giving and an amazing line-up of artists get to give us an incredible show."

Last year's event raised over 76million dollars for several charities, although organisers hope to beat that this year.