The US has announced that it has formed a five-member military tribunal to try terror suspects held at Guantanamo Bay.
Guantanamo detainees can challenge their detention
Retired Colonel Peter Brownback is to be presiding officer - or judge - the Pentagon said in a statement.
No date has been set, but a Pentagon spokesman said they were aiming to hear the first case by the end of the year.
David Hicks of Australia, Ali Hamza Ahmed Sulayman al-Bahlul of Yemen and Ibrahim Ahmed Mahmoud al-Qosi of Sudan have already been charged.
It was unclear whose trial would take place first.
Tuesday's appointment is a significant step towards actually holding the first military commissions or tribunals at Guantanamo Bay, says the BBC's Pentagon correspondent Nick Childs.
The move comes a day after the US Supreme Court ruled that the detainees at Guantanamo are entitled to challenge their detentions in a US court - seen as the biggest legal setback to President Bush since his war on terrorism began.
Nearly 600 detainees from 40 countries are currently being held at the Cuba base. Some have spent more than two years in captivity without being charged.
Colonel Brownback has 22 years of experience as a judge advocate and nearly 10 years of experience as a military judge, according to a Pentagon statement announcing his recall to active duty.
The statement did not identify the other panel members - all military officers.
"The presiding officer will be contacting attorneys in the cases in the near future to set an initial trial schedule," it said.
Australia's David Hicks may be the first to be tried
"This is an important first step," Air Force Major John Smith said, quoted by the Associated Press news agency.
The Pentagon insists the military tribunal process does provide for a full and fair trial, a contention rejected by critics and UK Attorney-General Lord Goldsmith.
The fact that these first tribunals - or military commissions as they are called - involve only a five-member panel underlines that the death penalty is not an option for sentencing, even if the defendants are found guilty, our correspondent says.
On Monday, by a margin of six to three, the US Supreme Court decided that the hundreds of prisoners being held at Guantanamo Bay did have a legal right to challenge their captivity.
The ruling passes no judgment on the guilt or innocence of those being held, but it does open the possibility that hundreds of appeals will now be launched in US courts on behalf of the detainees.