SAN JUAN, Puerto Rico -- The new admiral in charge of the Guantánamo Bay prison is seeking to impose significant changes to communications between lawyers and prisoners facing war-crimes charges at the U.S. Navy base in Cuba, The Associated Press has learned.

The proposed changes, contained in a 27-page draft order, have sparked a backlash from the Pentagon-appointed attorneys representing the five Guantánamo prisoners charged in the Sept. 11 attacks. They say the new rules would violate attorney-client privilege and legal ethics and deprive the prisoners of their constitutional right to counsel.

The order is still in draft form and has not yet been signed by the commander, Navy Cmdr. Tamsen Reese said Tuesday. Reese, the detention center spokeswoman, said the commander was not immediately available for an interview.

Lawyers for the Sept. 11 prisoners received the draft order from the commander, Navy Rear Adm. David Woods, on Dec. 22 and were told to sign an agreement to abide by the rules within 48 hours.

Instead, they sent a written response contending that requiring them to abide by such rules in order to see their clients was illegal.

“This requirement, as a precursor to engaging in client communications, interferes with the attorney-client relationship, compels counsel to violate ethical obligations, and therefore renders it impossible for counsel to effectively represent our clients,” they wrote, appealing for more time to review the proposed order.

The memo was signed by at least one member of each legal team representing the five prisoners, according to a military official who spoke on condition of anonymity because the document had not been publicly released.

The five prisoners accused of helping to organize the Sept. 11 case are expected to be arraigned at the base in 2012 in what would be the most high-profile U.S. war crimes tribunal since the World War II era. The five, including the self-proclaimed mastermind of the attacks, Khalid Sheikh Mohammed, are facing charges that include murder and could be sentenced to death if convicted.

The Sept. 11 trial has been delayed for years by legal challenges and a dispute between members of Congress and the White House over whether it should be held in a civilian court on the U.S. mainland or in a tribunal at Guantánamo. A dispute over communications rules between prisoners and their lawyers could add another delay.

The most significant disagreement is over the handling of legal communications, which are typically sent by courier from the defense lawyers, who are based in the Washington area, and the prisoners at the base on the southeastern corner of Cuba.

Under the new rules, a “privilege team,” which would include Department of Defense and law enforcement officials, would conduct a security review of all communications to the prisoners, according to the memo. The lawyers say such a review is unnecessary, since they all have security clearances and know not to release classified information, and also overly intrusive.

They say it would be impossible for Woods to ensure that these officials do not share this information with the prosecution or others because the members of the team wouldn’t be under his command.

The chief defense counsel of the military tribunals, Marine Corps. Col. Jeffrey Colwell, said he shares the concerns of the attorneys in the Sept. 11 case. He also objects to a provision in the new rules that would allow detainees to receive only letters from their lawyers and not any supporting documents such as legal motions or articles about their case.