He has been out of sight since his capture by US forces six months ago, but Saddam Hussein has emerged as one of the most visible symbols of the delicate and complex task of transferring power by month’s end to the new Iraqi government.

International and military law require that the former Iraqi leader — now held by Americans as a prisoner of war, in an undisclosed location — must either be charged with a crime or freed when US occupation ends on June 30. But the Iraqi tribunal that is expected to bring a war-crimes case against Saddam still is far from operational, and President Bush this week said he would transfer custody of the former leader from American to Iraqi control only when it was clear that Saddam would be securely imprisoned and stand trial.

No one expects Saddam to walk free when the June 30 deadline arrives. But the limbo surrounding his legal future illustrates the tensions surrounding the most high-profile detainee of the war in Iraq and the difficulties of launching a revamped Iraqi justice system, legal experts say.

“Obviously, this has been on low boil for quite a while, and now the issue of transfer of custody has really pushed it to the forefront,’’ said Neil J. Kritz, who directs the Rule of Law Program for the US Institute of Peace in Washington, D.C., and who has worked closely with the fledgling Iraqi tribunal expected to try Saddam.

“Quite frankly, there is an enormous amount that needs to be done just to build the institution,’’ Kritz said. “And you want to make sure when you’re doing something as momentous as bringing charges against Saddam Hussein that you do it right, and you make it airtight.’’

Questions of custody and criminal charges do not apply only to Saddam. The US military is holding as many as 5,000 Iraqi detainees who could face trial in Iraqi courts.

The country’s Interim Prime Minister Iyad Allawi has said that the new government would take control of Saddam and all other Iraqi detainees as soon as possible after the country regains sovereignty on June 30 and was negotiating with US authorities on the best way to do that.

Both governments face time pressures imposed by the Geneva Conventions as well as scrutiny regarding how well those rules are adhered to in the aftermath of the Iraqi prisoner-abuse scandal at Abu Ghraib, where seven US soldiers were charged with mistreating detainees.

The International Committee of the Red Cross pointed out this week that the Geneva Conventions require that Saddam be freed if he is not charged with a crime by the time the US occupation ends June 30. The Defense Department in January classified Saddam as a prisoner of war, because he was the leader of the old regime’s military forces in Iraq.

Diane F. Orentlicher, an international law professor at American University, said the US government faces different options for handling custody of Saddam after the transfer of power.

US authorities could charge Saddam directly with war crimes, Orentlicher said, but she discounted that possibility as remote. Since his capture in December, authorities in the United States and in Iraq have emphasized the importance of a transparent trial, held in Iraq to hold Saddam accountable for human-rights violations under his regime.

A more likely scenario, Orentlicher said, is that authority over Saddam will be transferred to Iraqi authorities who, in turn, can request that he remain under the guard of American soldiers. She said even if the war-crimes tribunal in Iraq is not fully operational, Saddam could be charged by the country’s central court and his case could later be transferred to the tribunal.

In Iraq, a spokesman for the occupation suggested this week that Saddam could remain a prisoner of war after June 30, because hostilities are expected to continue. And a resolution passed last week by the United Nations Security Council stated that a multinational force would continue to detain individuals in Iraq after June 30, as well as detain new individuals “where it is necessary for security purposes.’’