U.S. defense officials acknowledge that a draft Pentagon report says military planners had less time to prepare for postwar operations in Iraq because the actual combat phase went so quickly.

Defense officials stress that the report prepared for the military's Joint Chiefs of Staff is only a draft and they say it has not been reviewed nor approved.

But they acknowledge the classified document does link postwar difficulties in Iraq to a rushed and inadequate planning effort before the fighting began.

Still, the officials, speaking on condition of anonymity, deny the report is intended as a criticism of pre-war preparations. Instead, they describe it as a review intended to assist in future operations.

The secret assessment was first reported in the Washington Times newspaper, which published excerpts from the document.

The excerpts include one which describes as inadequate military planning for the so-far fruitless hunt for weapons of mass destruction in Iraq.

Word of the draft report's existence surfaced the day after a former Army Secretary, Thomas White, also criticized the Bush administration's postwar efforts in Iraq as totally inadequate.

Mr. White's views are contained in a new book, Reconstructing Eden, which reviews preparations for the Iraq war and offers a plan for rebuilding the country.

A news release on the publication hails the conduct of offensive operations during the war, but describes plans for peace in Iraq as non-existent.

In a related development, a new report by the Congressional Budget Office has warned the U.S. military may have difficulties sustaining its current troop levels in Iraq beyond early next year.

In a written response, a defense spokesman, Colonel Jay DeFrank, said the Pentagon is continuously examining troop level requirements to ensure military commanders in Iraq have the forces they need.