"An intense period of activity is going on. Many teams are out," said Caroline Cross, spokeswoman in Baghdad for the UN Special Commission (Unscom) charged with disarming Iraq.

Iraq's Foreign Minister Mohammad Said al-Sahhaf said a team of 39 inspectors flew in on Monday, but Ms Cross said the figure was exaggerated.

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UN officials will carry out "challenge" inspections over the next few days.

"They're about to start a series of inspections which will be the last piece for us to test whether or not Iraq has kept its promise of full co-operation," the United Nations chief weapons inspector, Richard Butler said.

Mr Butler is completing a report which could decide whether Baghdad has done enough to allow talks on the lifting of sanctions and an end to threats of aerial bombardment by western powers.

Co-operation in danger

Tariq Aziz: Iraq will co-operate if sanctions go

Iraq, in the meantime, has warned that its current co-operation with the inspectors, agreed just hours before a planned allied attack, will not last forever.

"If they want the Special Commission to continue their inspections, the Americans must decide to stop sanctions against Iraq," said Iraqi Deputy Prime Minister Tariq Aziz after talks with Russian officials in Moscow.

Mr Aziz, who had earlier met Russian Premier Yevgeny Primakov and Foreign Minister Igor Ivanov, also accused the US of intervening in Unscom's work.

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"The Americans do not want sanctions against Iraq lifted because they want the regime overthrown," Mr Aziz said.

"The special commission is deliberately slowing down its work, making forgeries and inventing crises at each stage."

Threats and diplomacy

Following a last minute resolution of the last conflict over the weapons inspections, the US and the UK warned Iraq that any future suspension of co-operation would, without further warning, lead to military retaliation.

Military strikes: Forces prepared

The Iraqi leadership shut down inspections in October, but reversed course on 14 November.

Mr Aziz, however, said that Iraq's decision to continue to co-operate "was not due to American threats but the results of the mediation efforts of Boris Yeltsin, (UN Secretary-General) Kofi Annan and other countries."

Kofi Annan, at a meeting of Gulf leaders in Abu Dhabi, has held out the prospect of a comprehensive review of sanctions - but only if Iraq continues to comply and co-operate on weapons inspections.

Unscom must certify that Iraq has eliminated its nuclear, biological and chemical weapons and long-range missiles before economic sanctions imposed after Baghdad's 1990 invasion of Kuwait can be lifted.