The panel conducting the probe said the committee, chaired by a former head of Britain's civil service, Lord Butler, would meet in private to avoid giving a partial or distorted public impression of the evidence.

The committee also said on Thursday it would not discuss its work before it published its final report. It will start hearing evidence in April and aims to report by the summer.

The panel will focus principally on the way intelligence was gathered rather than on the actions of individuals.

Following the announcement, Britain's opposition Liberal Democrats said the move vindicated their decision not to take part in the inquiry.

'Predictable' move

The party's foreign affairs spokesman Menzies Campbell said: "This entirely predictable announcement justifies the Liberal Democrat decision not to endorse, nor provide a member for, the Butler review."

Charles Kennedy, leader of the Lib Dems, had already said his key requirement was that the inquiry should also investigate the judgements which were made by politicians about intelligence assessments.

"This entirely predictable announcement justifies the Liberal Democrat decision not to endorse, nor provide a member for the Butler review."

Menzies Campbell,
Lib Dem foreign affairs spokesman

Speaking last week, he said: "The remit for this new inquiry is... unacceptable. An inquiry which excludes politicians from scrutiny is unlikely to command public confidence.

"Politicians should always be willing to answer for their judgement and their competence to the public.

"There is now widespread public disbelief about the stated reasons for our participation in the war in Iraq. That disbelief is undermining public trust in the office of the Prime Minister. 

Iraq war

"The way to re-establish that trust would be to have an inquiry which addresses the key questions directly and openly. It does not seem to me that this inquiry will be able to do that."

The issue of the Iraq war is continuing to dog Prime Minsiter Tony Blair despite the publication of a judicial report which exonerated the government of deliberately exaggerating information on Saddam's pre-war weapons.

Blair staked his political credibility on attempting to persuade a highly sceptical British public that war to remove the Iraqi president was needed last March because of his weapoins threat.

The prime minister's popularity has been severely dented as no such weapons have been discovered despite Saddam's capture by US troops in Iraq.

On 3 February Blair, under increasing pressure, announced that an investigation would be held into any intelligence failures.