The UN's chief weapons inspector has called on the United States and Britain to hand over intelligence relating to sites where they believe Iraq has weapons of mass destruction.

The most important thing governments like the UK or the US could give us would be to tell us sites where they are convinced [the Iraqis] keep some weapons of mass destruction Hans Blix

Hans Blix told the BBC that, if he knew where they thought Iraq was storing banned materials, he could send his inspection teams to check.

He said Western governments had intelligence sources not available to the United Nations - such as spies - but he was not receiving as much support as he would like.

The US and UK, meanwhile, raised the military pressure on Iraq with Prime Minister Tony Blair telling British troops to prepare for war and the Pentagon escalating plans to send more troops to the region next month.

The US is also putting forward its own proposals to Mr Blix, calling for inspectors to bring Iraqi scientists out of the country so they can be interviewed about Baghdad's weapons programmes.

Both Britain and the US have said Iraq's 12,000-page arms declaration is incomplete, with Washington accusing Baghdad of a "material breach" of UN resolutions - a path which could lead to war.

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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Mr Blix told the UN Security Council that Iraq's declaration did not contain the necessary evidence that known weapons of mass destruction had been destroyed.

He said he would report again on 27 January.

Baghdad produced its document in accordance with a Security Council resolution passed last month which threatens "serious consequences" if Iraq fails to comply with disarmament demands.

Mr Blix told the BBC that the onus should be on Iraq to back up its claims that it has no banned chemical, biological or nuclear weapons with hard evidence.

But, in the absence of that disclosure, and with Washington and London saying that Baghdad was blatantly lying - greater co-operation with Western governments was the inspectors' aim.

Eavesdropping evidence

"The most important thing governments like the UK or the US could give us would be to tell us sites where they are convinced [the Iraqis] keep some weapons of mass destruction - this is what we want," he said.

Target sites would help to make the best use of the inspection team's time

"We get a lot of briefings about what [the US and UK] believe that the Iraqis have, but of course what you really need is an indication of a place where things are stored, if they know it.

"They have all their methods to look, listen to telephone conversations, they have spies, they have the satellites etc, so they have a lot of sources which we do not have," he said.

Mr Blix said he had asked for help from US Secretary of State Colin Powell and UK Foreign Secretary Jack Straw and hoped a list of suspect sites would come.

US plans

Mr Powell has said the US will provide inspectors with "every possible" assistance, and a BBC correspondent in Washington says this is likely to include high-quality intelligence.

US President George W Bush is expected to comment publicly for the first time on Iraq's weapons declaration on Friday, but Mr Powell has already made the administration's position clear.

He said omissions in the document meant Baghdad was "well on its way to losing this last chance" to avoid military action.

He said there were clear issues that needed to be addressed in the coming weeks.

• Iraq's declaration should continue to be examined
• Inspectors should interview scientists for first-hand information on weapons programmes outside Iraq, where they may speak freely
• Inspectors should intensify efforts inside, with the support of intelligence from Security Council members
• Consultation should continue on how to compel Iraq to disarm

Mr Blair used his Christmas message to the military to say no-one knew if war in Iraq would be necessary, but preparations had to be made, including the build-up of troops.

Washington is readying around 50,000 soldiers to go to the region next month - a deployment which would almost double its force there.