U.S. and Yemen remain at odds over a proposal to release more than one-third of the detainees from Guantanamo Bay, officials said Monday, even as the Bush administration wrestles with the future of the military prison.

About 100 of the approximately 270 prisoners remaining at Guantanamo Bay are Yemeni nationals. A U.S. delegation visited the capital city of San'a last week to discuss the possible transfer of a few detainees to Yemen. Yemeni officials hoped to negotiate the release of all but the most dangerous prisoners.

"There is no progress at all," said Waleed Alshahari, an official following the talks for the Yemeni Embassy in Washington. "The situation remains as it is."

The future of Guantanamo Bay has been in doubt since the Supreme Court ruled last month that detainees have the right to challenge their imprisonment in U.S. courts. A deal with Yemen could dramatically shrink the inmate population before the Bush administration is forced to explain to federal judges why the detainees are being held.

State Department spokesman Sean McCormack said the U.S. and Yemen had "good discussions, but there's still work to be done in that regard." Another U.S. official, speaking on condition of anonymity to describe the private negotiations, said prospects were slim for an agreement any time soon.

Meanwhile, the court process begins Tuesday with a hearing in Washington. Under a proposed schedule to be discussed Tuesday, judges could begin reviewing evidence against some of the detainees within weeks. If judges decide there is not enough evidence, they could order some detainees released, but it would likely be up to the Bush administration to determine where to send them.

Despite White House claims that suspected terrorists could end up walking the streets of U.S. cities, judges generally don't have the authority to order a foreigner to be brought into the U.S., and a federal appeals court already refused to say otherwise.

The negotiations with Yemen hinge on what will happen to the detainees once they are returned to Yemen. The Bush administration wants to be sure that dangerous prisoners are not freed and that prisoners are held in humane conditions. Yemen proposes charging some detainees in its court system and supervising others as part of a "rehabilitation program."

"There are a lot of people there that have nothing to do with anything. And there are some people who have blood on their hands," said Mohammed Albasha, a spokesman for the Yemeni Embassy. "You cannot put both groups together."

U.S. negotiators hoped to agree on a trial program, in which a few Yemeni detainees are repatriated. If successful, it could be expanded over time.

The U.S. is not confident, however, in Yemen's ability to ensure that detainees are not freed. In the past, suspects have escaped from Yemeni prisons and, in some cases, it was unclear whether they were simply released.

Given those concerns, one U.S. official — the same one who said an imminent deal is unlikely — said it could take up to two years for Yemen to establish the kind of safeguards the U.S. wants to see before transferring prisoners.

Such a timeline would not help the Bush administration as it prepares to go to court. Albasha predicted judges would determine some Yemeni detainees were being improperly held, forcing the U.S. to decide soon how to continue.

The Guantanamo Bay discussions come amid what Yemen's foreign minister recently called a crisis in relations between the two countries. Yemen says its constitution prohibits the extradition of two al-Qaida suspects wanted by the FBI in connection with the 2000 bombing of the USS Cole.

Also Monday, the State Department announced the July 2 transfer of two detainees to Algeria and reiterated President Bush's desire to close Guantanamo Bay.

"The United States has no desire to hold detainees any longer than necessary and is making tremendous strides to ensure that those individuals who no longer need to be held by the United States are transferred to their home countries," said State Department spokesman Rob McInturff.