Evidence on Iraq Challenged

A key piece of evidence in the Bush administration's case against Iraq is being challenged in a report by independent experts who question whether thousands of high-strength aluminum tubes recently sought by Iraq were intended for a secret nuclear weapons program.

The White House last week said attempts by Iraq to acquire the tubes point to a clandestine program to make enriched uranium for nuclear bombs. But the experts say in a new report that the evidence is ambiguous, and in some ways contradicts what is known about Iraq's past nuclear efforts.

The report, from the Institute for Science and International Security, also contends that the Bush administration is trying to quiet dissent among its own analysts over how to interpret the evidence. The report, a draft of which was obtained by The Washington Post, was authored by David Albright, a physicist who investigated Iraq's nuclear weapons program following the 1991 Persian Gulf War as a member of the International Atomic Energy Agency's inspection team. The institute, headquartered in Washington, is an independent group that studies nuclear and other security issues.

"By themselves, these attempted procurements are not evidence that Iraq is in possession of, or close to possessing, nuclear weapons," the report said. "They do not provide evidence that Iraq has an operating centrifuge plant or when such a plant could be operational."