The US Defence Department has said it would like to close down the Guantanamo Bay detention facility on the Cuban island but, it cannot be done until a statutory status for the detainees are found.

"The President said he wants to close Guantanamo. Obviously, a lot of people on the Hill want to close it," the US Defence Secretary Robert Gates said.

Gates said, the biggest challenge is finding a statutory basis for holding prisoners, who should never be released and who may or may not be able to be put on trial.

"And I think that, this is the challenge that faces both the administration and the Congress," he said.

The United States is currently holding about 350 persons -- from different parts of the world -- on charges related to terrorism, many of whom have been picked up in the aftermath of the invasion of Afghanistan in 2001.

Human rights activists and groups have consistently protested their detention claiming that most of those held have not been charged with anything specific and are routinely denied their basic rights.