Agreeing in part with the United States, UN weapons inspectors reported yesterday Iraq had not accounted for stocks of anthrax and had failed to declare what appeared to be mobile biological arms labs.

But the 45-page report from chief UN inspector Hans Blix to the Security Council did not draw the sweeping conclusions made by the United States and Britain to justify the invasion of Iraq in March. Both nations contend former President Saddam Hussein hid stockpiles of weapons of mass destruction but have found none and the new UN report does not identify any.

However, Blix said photos of mobile laboratories Washington says could make biological weapons were unlike any vehicle Iraq has admitted owning in its reports to the inspectors.

"None of the types of mobile laboratories described in the media in April-May 2003 as found in Iraq matched the description of mobile facilities provided by Iraq" to the UN Monitoring Verification and Inspection Commission (UNMOVIC), Blix said.

Analysing information before the inspectors were withdrawn in March and laboratory tests since then, the Blix report said Iraq's data "does not resolve the question regarding the total quantity of anthrax produced and destroyed by Iraq."

Blix said his inspectors from UNMOVIC also were dissatisfied with data on the deadly nerve gas VX.

Iraq, the report disclosed, had given inspectors documents right up to the start of the war, including on the import of 380 Volga engines and sophisticated equipment for missiles. But Baghdad hid data on the origin of the materials.

However, Blix said the United States and Britain had ignored his commission since the end of the war.

"The findings and experiences of the relevant units established by the coalition have not been available to the commission except through public media reports," Blix said in the report. "Nor have these units or the coalition requested any information or assistance from the commission.

Blix, who is leaving his post at the end of June, said inspectors were ready to resume work within two weeks if needed, including 30 staff members in New York. UN inspectors returned to Iraq last November and were pulled out in March.

The future of UNMOVIC is a point of controversy in the Security Council with all members except the United States anxious to have the inspectors return to check on any banned chemical, biological or ballistic missiles.