Michael Winterbottom's film The Road to Guantanamo has drawn cheers after being screened at Berlin Film Festival.
Michael Winterbottom's other credits include A Cock And Bull Story
The film tells the true story of three British Muslims held at the US prison camp for two years before being released without charge.
The depiction of the Guantanamo Bay camp in Cuba was chosen by festival director Dieter Kosslick.
The Road to Guantanamo has now emerged as one of the front runners for prizes at the festival.
The film gets its world premiere on Wednesday.
Speaking after the screening, Winterbottom - who won Berlinale's Golden Bear award for best film in 2003 - told reporters that his film was not anti-American.
"The point of making it [the film] is to remind people about how bizarre it is that somewhere like Guantanamo exists.
"I don't think the film is anti-American in any general sense.
"We're not trying to say Americans are bad... What we're saying is that just the fact of Guantanamo's existence is shocking and terrible and it shouldn't be there."
The film script was based on interviews with the so-called "Tipton Three" - Rhuhel Ahmed, Shafiq Rasul and Asif Iqbal - who were inmates at Guantanamo before being released in 2004.
Mr Ahmed and Mr Rasul were in Berlin to promote the film.
It is to become the first simultaneous cinema, DVD and online release, according to Screen Daily.
The film will be shown on Channel 4 on 9 March and released on the other platforms the following day.
The Berlin festival runs until Sunday, when its top prize, the Golden Bear, will be announced.