The Government today requested the release of Omar Deghayes from Guantanamo Bay, the Foreign Office said.
He is one of five UK prisoners who the Government want released.
The news follows a long-running campaign, Justice for Omar, run by The Argus, demanding justice for Omar, from Saltdean.
We said he should receive a fair trial or be released.
The Foreign Secretary and Home Secretary are seeking the release of the men who were legally resident in the UK before their detention.
Foreign Secretary David Miliband has written to US Secretary of State Condoleezza Rice to formally make the request.
The men, who have been named as Shaker Aamer, Jamil El Banna, Binyam Mohamed, Abdennour Sameur and Omar Deghayes, are not UK nationals but had been granted refugee status, indefinite leave or exceptional leave to remain before they were detained.
By January 2005 the Government had secured the release and return of all UK nationals detained at the centre but had not sought the release of this group of men.
The Foreign Office said it had reviewed its approach to the group in the light of its aim to see the closure of the centre and recent steps taken by the US government to reduce the numbers of detainees held there.
In a statement, the Foreign Office said: "The Foreign Secretary and Home Secretary have reviewed the Government's approach to this group of individuals in light of these ongoing developments, our long-held policy aim of securing the closure of Guantanamo Bay, and the need to maintain national security.
"They have decided to request the release and return of the five detainees who have links to the UK as former residents, having been granted refugee status, indefinite leave or exceptional leave to remain prior to their detention."
The statement added: "Our representations are limited to those with links to the United Kingdom as evidenced by their past lawful residence here."
The Foreign Office cautioned that the release and return of the men may take some time.
"The Government will, of course, continue to take all necessary measures to maintain national security.
"Should these men be returned to the UK, the same security considerations and actions will apply to them as would apply to any other foreign national in this country," the statement said.
The Government's move the seek the release of the men was welcomed by civil rights groups.
James Welch, legal director for campaign group Liberty said: "This change of policy is extremely welcome, especially if it signals a bigger change of approach on both sides of the Atlantic.
"Surely US and UK governments need no further evidence that internment, kidnap and torture have been completely counterproductive in the struggle against terrorism.
"It's high time that the special relationship returned to its original values of defending liberty rather than degrading it."
Last month Home Secretary Jacqui Smith was told by the High Court that she had until 4pm on August 9 to decide whether one of the men, 45-year-old Jamil El Banna, would be allowed to return to live in the UK following his release.
Mr Justice Beatson made the order as he gave Mr El Banna's solicitors permission to seek judicial review of the Government's failure to confirm that he would be allowed to return and live with his wife and five children - all British nationals - at their home in Dollis Hill, north west London.
His lawyers claim he has been unlawfully detained by the Americans in their "war on terror" for more than four-and-a-half years.
Mr El Banna was arrested on suspicion of having links to al Qaida in November 2002 during a visit to Gambia, west Africa.
He was taken by the Americans to their interrogation facility at the Bagram air base in Afghanistan, and then transferred to their detention centre at Guantanamo Bay, Cuba.
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