Binyam Mohamed could face the death penalty if found guilty
A UK resident detained at Guantanamo Bay has won a High Court ruling that the government should disclose material which he says backs his torture claims.
Binyam Mohamed, who is facing terrorism charges, says the documents support his case that the evidence against him has been obtained through torture.
Mr Mohamed, 30, has been held at the US military prison in Cuba for four years.
The judges said the information relating to him was "not only necessary but essential for his defence".
Mr Mohamed has been represented by the legal charity Reprieve while in Guantanamo Bay.
Reprieve director, Clive Stafford Smith, said the ruling was "a momentous decision".
The United States accuses Mr Mohamed of conspiring with al-Qaeda leaders to plan terror attacks on civilians.
He is facing a military trial in the US and could even be given the death penalty if he is found guilty.
His legal team is seeking the disclosure of material that he says will help defend the charges he faces.
Mr Mohamed moved to the UK as a refugee from Ethiopia when he was 15 and was arrested in April 2002 in Pakistan.
The next step is for the British government to demand an end to the charade against him in Guantanamo Bay, and return him home to Britain
He claims to have spent 18 months in Morocco, where he says he was tortured, before being flown to an alleged CIA-run site in Afghanistan and then later transferred to Guantanamo.
Mr Mohamed, who previously lived in west London, alleges his charges are based on confessions extracted by torture and ill-treatment.
Lord Justice Thomas and Mr Justice Lloyd Jones were told in a previous hearing that the US authorities have denied subjecting Mr Mohamed to extraordinary rendition or torture.
Richard Stein, of solicitors Leigh Day & Co, who represent Mr Mohamed, said the judgement "reflects the abhorrence of decent society at the methods employed by the United States government in the supposed 'war on terror'.
"We can only hope that the foreign secretary will now reflect on this judgment and provide direct assistance to Binyam's defence team."
Mr Stafford Smith added: "Compelling the British government to release information that can prove Mr Mohamed's innocence is one obvious step towards making up for the years of torture that he has suffered.
"The next step is for the British government to demand an end to the charade against him in Guantanamo Bay, and return him home to Britain."