The US is preparing to release or transfer many of the 549 detainees who are currently being held at the country's naval base at Guantánamo Bay in Cuba, a senior US defence official has told the Financial Times.

The official said "a significant portion will gradually be transferred or released" as part of a restructuring of the camp. This will include the construction of a new prison at the base, in which the US intends to hold long-term prisoners.