The United States has renewed calls for the United Nations weapons inspections in Iraq to be conducted more aggressively.

This is the biggest manoeuvre exercise since the Gulf War Major General Buford Blout

US National Security Adviser Condoleezza Rice said she wanted the number of inspectors on the ground to be increased to 250 or 300 - from a current total of just over 100.

Other senior US officials also want the inspections to be more vigorous, and to include simultaneous visits to a wide range of sites.

The calls come as US forces are pressing ahead with plans for war in Iraq, with a big military exercise in Kuwait.

IRAQI MATERIAL UNACCOUNTED FOR

Nearly four tons of VX nerve agents Growth media for 20,000 litres of biological warfare agents 15,000 shells for use in biological warfare 6,000 chemical warfare bombs Nuclear information

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But the Russian Foreign Minister, Igor Ivanov, has reiterated that the main task in Iraq is to ensure Baghdad no longer has weapons of mass destruction, and that any other goals are outside Russia's interests.

In Iraq itself, weapons inspectors visited 12 sites on Saturday - including missile production plants at Taji, north of Baghdad and Qaqaa, south of the Iraqi capital.

Washington says it will share intelligence with the inspectors, identifying specific locations where weapons of mass destruction may have been stored or produced.

Chief UN arms inspector Hans Blix has criticised the US for not sharing sensitive information.

American officials have been reluctant to do so, believing it could easily fall into the hands of the Iraqis.

The BBC's Nick Bryant in Washington says the Americans will continue to withhold their best or most specific intelligence - but it seems they are now prepared to hand over satellite pictures identifying up to five suspicious sites.

Ready for battle

In Kuwait, more than 12,000 US troops, supported by hundreds of armoured vehicles and helicopters, are taking part in a military exercise close to the Iraqi border.

US forces in the Gulf are getting ready

"This is the biggest manoeuvre exercise since the Gulf War," Major General Buford Blout told the Associated Press news agency.

Tanks swept through the wind-swept sands on the first of two days of exercises.

Soldiers have painted on their rifle barrels slogans such as: "All the way to Baghdad," as well as the flight numbers of the jets hijacked in last year's 11 September attacks on New York and Washington.

Talking of the prospect of fighting Iraqi soldiers, Lieutenant Ryan Kuo said: "I kind of feel sorry for them. It is not like 10 years ago. The weapons we have now don't miss."

Journalists and television crews have been invited to witness the exercise in what correspondents say is a move to increase pressure on the Iraqi Government.

The US military has also begun dropping tens of thousands of information leaflets over Iraq, in preparation for a possible military offensive.

Blix is due to report by 27 January

President Bush has cancelled a trip to Africa planned for January in what is being as a sign of further preparation for war.

In his pre-Christmas radio address on Saturday, Mr Bush asked Americans to remember US troops abroad standing between "Americans and grave danger".

On Thursday Washington declared Iraq to be in material breach of the UN resolution on disarming Iraq.

Mr Blix is due to present a full report on the work of his teams to the UN by 27 January.