SAN JUAN, Puerto Rico - As the U.S. military prepares for the first war crimes trial under President Barack Obama, its most high-profile case against the planners of the Sept. 11 attacks is stuck in political and legal limbo.

Canadian prisoner Omar Khadr, accused of killing an American soldier during a raid on an al-Qaida compound, is scheduled to go to trial Aug. 9 at the U.S. base in Cuba.

But Khalid Sheikh Mohammed, the professed mastermind of the attacks, and four alleged accomplices are still sequestered at Guantanamo without charges. The Obama administration, after months of review, hasn't made a decision on whether to seek a military or civilian trial.

It's a delay that has angered relatives of Sept. 11 victims. It also has created an unusual situation: Previous war-crimes proceedings, in which Mohammed boasted of his role in the attacks and said he wanted to plead guilty, have essentially been erased. No U.S. officials will say what the plans are for the five men who were transferred in 2006 to Guantanamo from secret CIA custody.

"There's no case, there's no judge, there's nothing," said Navy Lt. Cmdr. Richard Federico, a military lawyer appointed to defend alleged plotter Ramzi bin al Shibh. "They are back into the black hole."

Attorney General Eric Holder announced in November the trial would be moved to federal court in New York. But the administration backtracked and put the issue under review after local officials objected to the costs and potential security threat.

The military and justice department refer questions about the status to the White House, which said in March a decision was weeks away. An Obama administration official, speaking on condition of anonymity, told The Associated Press on Friday it is still reviewing the venue and forum for the trial.

Lawyers for the Sept. 11 defendants and other observers doubt an announcement will be made before November elections, because moving them to the United States and keeping them in Guantanamo for a military trial are both politically unpopular choices.

"Why would you want to pay this political price in the three months before this election which you are expecting to do badly in?" said Benjamin Wittes, a senior fellow and terrorism specialist at the Brookings Institution.

The administration official, who spoke on condition of anonymity because the review is ongoing, said the election does not have any influence on the process. The official said the security and cost concerns of state and local officials in New York are being taken into account.

Dominic Puopolo Jr., a Miami computer consultant whose mother was killed in the Sept. 11 attacks, attended the trial in Germany of a Moroccan man accused of aiding the plotters and still hopes to see Mohammed and his co-defendants prosecuted as well - before the 10-year anniversary in 2011.

"I'm incredibly disappointed with the way the Obama administration has handled this," said Puopolo, whose mother was on board the American Airlines flight out of Boston that the hijackers crashed into the World Trade Center on Sept. 11.

During his presidential campaign, Obama criticized the war crimes tribunals, known as military commissions, that began under his predecessor. But he worked with Congress to adopt changes. He said he wants to keep the tribunals as an option for some prisoners, including Khadr, as part of a plan to close the Guantanamo detention center, where the U.S. holds about 175 men.

Even with the changes, the military commissions are unpopular with some Obama supporters. The American Civil Liberties Union said in a report Thursday that there have been "procedural improvements," but the tribunals could still convict someone with hearsay evidence obtained coercively, or based on testimony from detainees who are not available for cross-examination.

In the Khadr case, critics oppose the war crimes trial because the defendant was 15 when he allegedly threw the grenade that killed U.S. Army Sgt. 1st Class Christopher Speer of Albuquerque, New Mexico, during a raid on a al-Qaida compound in Afghanistan in 2002.

"Unless the president ends this travesty of justice, the Obama military commissions will forever be remembered for prosecuting a child," Army Lt. Col. Jon Jackson, Khadr's Pentagon-appointed lawyer, said Saturday.

The military says it's a war crimes case because he was not a legitimate soldier. Khadr faces up to life in prison if convicted of murder in a trial that could last several weeks.

The Sept. 11 case is vastly more complicated. For one thing it is a capital case, with nearly 3,000 victims. Legal experts say it's unclear whether the rules of military commissions permit a defendant to plead guilty and be executed, as Mohammed and his co-defendants have indicated they want to do.

Wittes noted that any choice has potential costs - and potential policy benefits. A successful trial in federal court or the military commission would help clarify legal questions and create a framework for trying other Guantanamo prisoners, helping to close the detention center.

"There is nothing defensible about not making a decision and letting the issue fester," he said.

As the debate over what to do goes on behind closed doors, military lawyers still visit the Sept. 11 defendants, even though the men have said they want to act as their own lawyers during any trial.

Navy Lt. Cmdr. James Hatcher, meets every three weeks with his appointed client, Waleed bin Attash, a Yemeni who allegedly ran an al-Qaida training in Afghanistan, where two of the 19 hijackers were trained. He can't provide any details under the security rules.

"It's obviously in a holding pattern," Hatcher said. "I can tell you we are preparing on both fronts, whether it goes to federal court or to military court."