WASHINGTON (AP) — A federal appeals court is inviting prosecutors to find substitutes for classified material so that the case of accused terrorist Zacarias Moussaoui can proceed.

The case is on hold while the 4th U.S. Circuit Court of appeals and a trial judge decide whether Moussaoui is getting enough information to craft a defense.

The 4th Circuit, in Richmond, Va., on Tuesday ordered a temporary halt to a pretrial dispute on Moussaoui's access to classified material. Instead, it told U.S. District Judge Leonie Brinkema to determine whether a compromise is possible.

Brinkema has questioned whether the government can prosecute the case after imposing a "shroud of secrecy" on documents and witnesses that might aid Moussaoui's defense.

"The government is to be given an opportunity to propose substitutions for the classified information authorized to be disclosed by the district court ... and the defendant and standby counsel are to be given an opportunity to respond to any proposed substitutions," the appeals court said in its two-page order.

Moussaoui, who is a French citizen, is representing himself and has no access to the large amounts of classified information prosecutors compiled. Lawyers appointed by the court to represent his interests have seen the material, but Moussaoui has refused to cooperate with them.

Moussaoui is the lone defendant in the United States charged as a conspirator with the Sept. 11 hijackers. The government said it would seek the death penalty if he is convicted of conspiracy to commit terrorism and hijack airliners.

The defendant has admitted he belongs to al-Qaida but denies he was part of the Sept. 11 conspiracy.

Brinkema issued a secret order on Jan. 31 that authorized disclosure of classified information and reportedly granted Moussaoui access to captured al-Qaida prisoner Ramzi Binalshibh -- an alleged coordinator of the attacks. The government's appeal of that order brought the case to the appellate court.

Moussaoui contends that Binalshibh, a suspected coordinator of the Sept. 11 attacks, and other al-Qaida captives can disprove the charge that he conspired with the attackers to commit terrorism.

On Monday the Justice Department, addressing Brinkema's concerns, told her in a written pleading that it was able to try Moussaoui in a civilian court while protecting his rights and government secrets.

That written pleading reaffirmed Attorney General John Ashcroft's objection to moving the case to military jurisdiction, even though some Pentagon and intelligence officials reportedly would prefer that option.

The 4th Circuit postponed oral argument on the government's appeal from early May to June 3. The appellate judges have closed proceedings to the public, although news organizations have asked that arguments on unclassified matters be conducted openly.

Brinkema scheduled a hearing May 7 to discuss proposed compromises. The proceeding will be held in private.