A leading senator and member of the Foreign Relations Committee has said that the US should close its detention centre at Guantanamo Bay.
Democrat Joseph Biden said the controversy over the military camp put Americans at risk from terrorism rather than protecting them from it.
He said the future of the centre needed to be examined.
Hundreds of alleged terrorism suspects have been held at the camp without charge for up to three years.
Guantanamo “has become the greatest propaganda tool that exists for recruiting of terrorists around the world and it is unnecessary to be in that position”, Mr Biden said.
“We should end up shutting it down, moving those prisoners,” he told ABC’s This Week programme.
“Those that we have reason to keep, keep. And those we don’t, let go.”
An independent commission should examine all the prisons in which the US detains those it deems terrorist suspects, he said.
The comments came two days after the Pentagon admitted that guards at Guantanamo Bay had desecrated the Koran.
Last month, Amnesty International called the detention centre for alleged terrorists “the gulag of our time“, referring to the system of forced labour camps in the Soviet Union in which millions of prisoners died.
US Defence Secretary Donald Rumsfeld said the charge was “reprehensible”.
Senator Biden, as a member of the opposition, can have only a limited impact on policy, says the BBC’s Adam Brookes in Washington.
But his words reflect an anxious debate here about the treatment of detainees and how it reflects on America’s image in the world, our correspondent says.