A federal judge gave the New York Times a brief reprieve from an order forcing it to identify confidential sources for columns about the 2001 anthrax attacks, but the paper could still face the possibility of being held in contempt of court as soon as tomorrow.

Judge Claude Hilton of Alexandria, Va., issued a two-day stay of a magistrate’s order that would have required the Times to name the sources by yesterday. The order came in a libel suit filed by a former Army scientist, Steven Hatfill, who claims he was defamed by five columns written by Nicholas Kristof in 2002.

According to a lawyer involved in the dispute, Judge Hilton said yesterday that he was still reviewing whether the Times should be compelled to identify the sources. He told attorneys that he planned to rule on the issue by Friday.

But the Times suffered a setback yesterday when Judge Hilton upheld a magistrate’s ruling denying its request to suspend action on the libel suit until the government completes its investigation into the anthrax mailings, which killed at least five people. While investigators searched a home and storage locker belonging to Mr. Hatfill, no criminal charges were brought.

The newspaper wanted to defend against the libel suit by gaining access to the records of the government probe, but the Justice Department has refused to cooperate. The magistrate assigned to the suit, Liam O’Grady, declined to force the disclosure of details of the investigation, which the FBI contends is ongoing.