Lawyers for five Guantanamo Bay prisoners charged over the September 11 attacks are asking a military court to put their legal proceedings on hold during the Muslim holy month of Ramadan.
The lawyers also ask that no court sessions be held on Fridays, when many devout Muslims seek not to work.
Defence lawyers argue in court motions that the court has an obligation to respect the men's faith and their need to fast and pray during Ramadan, which comes in late summer this year.
Prosecutors say any blanket restriction would make it too difficult to schedule hearings.
The five defendants include the self-proclaimed mastermind of the attacks, Khalid Sheikh Mohammed. They face the death penalty if convicted.
Their next hearings are scheduled to start on August 8, during Ramadan.