The United States army has begun a big military exercise in Kuwait, close to the border with Iraq.

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

It comes hours after US officials said 50,000 troops were being sent to the region to prepare for action against Saddam Hussein.

In Iraq itself, 10 teams of United Nations weapons inspectors resumed work on Saturday.

Washington now says it will share intelligence with the inspectors to help them find weapons of mass destruction.

Wind-swept sands

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

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The agency says thousands of troops are taking part, supported by hundreds of armoured vehicles and helicopters.

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.

Production plants

Across the border United Nations inspectors visited 12 sites on Saturday, Iraqi officials said.

The exercise lasts two days

They included missile production plants at Taji, 18 kilometres (11 miles) north of Baghdad and Qaqaa, 20km (12 miles) south of Baghdad, the AFP news agency said.

Another site was the premises of the Samarra pharmaceutical company.

Chief UN weapons inspector Hans Blix criticised the US for not sharing sensitive intelligence information, believing it could easily fall into the hands of the Iraqis.

But a BBC correspondent in Washington says the US is now prepared to hand over satellite imagery identifying up to five suspicious sites.

The Bush administration wants the inspectors to have a real opportunity to catch the Iraqis out, and American officials say they are willing to take a chance that revealed intelligence might be leaked, our correspondent says.

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

Blix is due to report by 27 January

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

UK Prime Minister Tony Blair told the country's armed forces on Friday that they, too, must be ready for a possible confrontation with Iraq.

In his first public response to Iraq's weapons declaration to the UN, Mr Bush told reporters on Friday that it was "not encouraging".

"We expect Mr Saddam Hussein to disarm," Mr Bush said.

"Yesterday was a disappointing day for those who long for peace," he added.

Chief weapons inspector Hans Blix is due to present a full report on the work of his teams to the UN by 27 January.