Documentary We Are Together (Thina Simunye), which won prizes at IDFA and Tribeca, is working with the ONE Campaign to promote the film in the US.

The film is already partnered with Alicia Keys' charity Keep A Child Alive and now is also working with Bono's ONE organisation, which fights AIDS and extreme poverty.

The film, directed by Paul Taylor and produced by Teddy Leifer for the UK 's Rise Films, tells the story of a choir formed by children in South Africa 's Agape Orphanage, most of whom have lost loved ones with AIDS.

'They sing their stories and that's what's so incredible,' Bono said after the film's screening at the Tribeca Film Festival. 'They sing themselves out of sorrow. It's a very joyful feeling throughout the film.'

Producer Teddy Leifer added: 'With ONE and Keep A Child Alive on board, our ability to reach audiences is really strengthened. We've got a great team and everyone's excited about the year ahead'.

Sales for We Are Together are handled by Annie Roney of ro*co, who expects to finalise a North American theatrical deal soon.

The project is also backed by HBO Documentary Films and the Channel 4 British Documentary Film Foundation.