Senior Airman Ahmad al Halabi, who faces life in prison if convicted, has been charged with espionage related to his work at the base where the US is holding 660 Muslims without charge.

The Syrian-American Halabi, who has denied the charges, was arrested in Florida in July and accused of carrying jail maps, letters and other sensitive documents from Guantanamo.

His military lawyer complained after the arraignment hearing at Travis Air Force base north of San Francisco the defence team had not been able to prepare because so much evidence remained classified.

"It's very frustrating," military defence attorney Major James Key said. "The defence has not been able to really be prepared to form a trial strategy at this point of time."

"The defence has not been able to really be prepared to form a trial strategy at this point of time"

Major James Key
Defence Attorney

Because of government-imposed restrictions on information, Key said he had not been able to "discuss the nuts and bolts of the case" with Halabi's civilian attorney.

Judge Col Barbara Brand also expressed concern about the slow pace of the proceedings.

"This young man has been in pre-trial confinement since 25 July," she said while setting the February deadline.

Halabi is one of four men, including another Arabic translator and a Muslim chaplain, charged in connection with their work at Guantanamo.