Michael Winterbottom journeyed from Pakistan to England twice

The channel is reported to have paid $200,000 (�132,000) for the film, which tells the story of two Afghani teenagers, Jamal and Enayatullah, who travel from Afghanistan to Britain to seek asylum.

The film was shot on digital video, using two boys who had never acted before.

It was unveiled at the London Film Festival last November, and won the Golden Bear at the Berlin Film Festival last month.

The film will be released in the US at the end of the year.

Redford's Sundance Channel, which show's alternative film, moved into theatrical distribution in January.

They set up a deal with the Loewe Cineplex chain, and their initial plan is to release four film in 10 key cities in the US.

Unscripted footage

After their theatrical run, the movies will be released on video under the Sundance Channel Home Entertainment label.

Winterbottom's film followed a "dummy run" the director undertook just weeks after the 11 September attacks on the US.

He then returned to a refugee camp in Quetta, Pakistan, and retraced the journey with two Afghani boys who lived in a refugee camp there.

He then shot largely unscripted footage on the road to the UK.

In a bizarre twist, Jamal Udin Torabi, one of the two actors, then undertook the journey for real and is currently seeking asylum in the UK.

"I hope when you watch this film you think 'our asylum policies are too restrictive'," Winterbottom told BBC News Online last year.

"I hope it will make people feel that the people that get here have made extraordinary efforts and we should welcome them.