"We found the weapons of mass destruction," Bush asserted in the Thursday interview, released Friday. "We found biological laboratories. You remember when Colin Powell stood up in front of the world, and he said, Iraq has got laboratories, mobile labs to build biological weapons. They're illegal. They're against the United Nations resolutions, and we've so far discovered two. And we'll find more weapons as time goes on. But for those who say we haven't found the banned manufacturing devices or banned weapons, they're wrong. We found them."

Bush's assertion, one of many recent administration statements shifting focus from Iraq's weapons to Iraq's weapons programs, indicated the president would consider its accusations justified by the discovery of equipment that potentially could be used to produce weapons. But the original charges against Iraq, presented to the United Nations and the American public, were explicitly about the weapons themselves.

According to the report, senior production officials at the research facility at Al Kindi said the trailers were used to produce hydrogen for use in artillery weather balloons. While acknowledging that the plants could be used for that purpose, intelligence officials said it was illogical and unlikely.

''The Iraqis had a motivation for inefficiently producing biological agent,'' one official said. ''They had no motivation for inefficiently producing anything else. If they wanted to produce hydrogen, they should have produced it efficiently.'' The official added that the facility was probably developed more for secrecy than for efficiency of chemical production.