Prime Minister Gordon Brown asked the United States on Tuesday to free five residents of Britain from the military prison at Guantanamo Bay - a policy reversal that was welcomed by the Bush administration.
The United States has been working to reduce the detainee population at Guantanamo with an eye toward closing the controversial detention center.
In some cases where a detainee is likely to be mistreated in his native country, the Bush administration has been appealing to nations with respected human rights records to take the detainees it does not intend to try in U.S. military courts.
U.S. officials said Tuesday that Brown's decision to ask for the transfer of the five British nationals, who are not citizens, was a positive step in broader efforts to cut back the number of inmates and eventually shut Guantanamo.
State Department spokesman Sean McCormack said the British request was being reviewed, and he encouraged Britain and other nations to accept more detainees.
About 360 people are being held at the prison.
The request from Brown contrasts with Tony Blair's government, which chose to secure the release of only nine British citizens and one resident who had provided help to British intelligence services. The Blair government refused to intervene in the plight of other British residents, saying it could not help noncitizens.
Foreign Secretary David Miliband wrote to Secretary of State Condoleezza Rice requesting the release of the five, the Foreign Office said Tuesday. It said U.S. steps to reduce the number of detainees at Guantanamo prompted a review of the British government's approach.
The men - Saudi Shaker Aamer, Jordanian Jamil el-Banna, Libyan-born Omar Deghayes, Ethiopian national Binyam Mohamed and Algerian Abdennour Sameur - had all been granted refugee status, indefinite leave or exceptional leave to remain in Britain before they were detained, the British government said.
Banna was arrested by Gambian authorities in November 2002, the rights group Amnesty International said. It said Deghayes and Aamer were captured in Pakistan in 2002.
The human rights group Reprieve said Mohamed was captured in Pakistan in April 2002 and held in Morocco for 18 months before arriving at Guantanamo. The circumstances of Sameur's arrest were not clear.