Lord Goldsmith, QC, said that his evaluation of the legal arguments for war, obtained by Channel 4 News, backed up the summary issued to Parliament which justified military action.

The leak looked set to ignite a firestorm under the issue of Mr Blair’s trustworthiness over events leading to the Iraq war as the general election campaign nears its climax. There were calls for Lord Goldsmith’s advice to Mr Blair to be published in full after the leaked summary showed that he believed that a second UN resolution was “the safest legal course”. Ten days later, after Britain and the US abandoned attempts to secure a second resolution, Lord Goldsmith gave a verbal summary to the Cabinet. In this, he said that the war would be lawful based on the “combined effect” of previous UN resolutions.

Families of British soldiers killed in Iraq said that the publication would assist an indictment that they planned to present at the High Court in London against Mr Blair today.

Michael Howard, the Tory leader, said: “We now know that the Attorney-General’s advice was full of qualifications and caveats. The Prime Minister has said that the Attorney-General’s advice given to the Cabinet ten days later was clear and he said the AttorneyGeneral did not change that advice. We now know the Attorney-General did change that advice and the question that has to be answered is what or who changed it.”

Sir Menzies Campbell, the Lib Dem deputy leader, added: “We have ten lost days between March 7 and 17 in the course of which the Attorney-General, who had previously been of the view that was of doubtful legality, somehow came to the view that war could be legal. Who did he meet and what influences were brought to bear on him?”

Channel 4 News published six paragraphs from the summary of Lord Goldsmith’s private advice to Mr Blair after months of clamour for the Prime Minister to publish it in full. It does not cover all of the six possible breaches of international law reported at the weekend, omitting the fear that British troops could be brought before the International Criminal Court.Lord Goldsmith’s statement last night read: “The document, published by Channel 4 News, so far from standing up the case of the Government’s critics, stands up the case the Government has been making all along. Contrary to the allegations that have persistently been made, it does not say the war was unlawful but confirms the conclusion I reached was that a sufficient basis for the use of force was established without a second resolution.”

In the Channel 4 document, Lord Goldsmith says that the wording of Resolution 1441 giving Saddam Hussein a last chance “leaves the position unclear” and that “arguments can be made on both sides”. He states that “a reasonable case can be made” that resolution 1441 is able to revive the threat of military intervention made in earlier UN resolutions. But he added that this would “only be sustainable if there are strong factual grounds for concluding that Iraq has failed to take the final opportunity”.

Showing his doubts about the case for war without a second UN resolution, he said that “a reasonable case does not mean that if the matter ever came before a court I would be confident that the court would agree with the view”. He said that without a second resolution explicitly authorising military action, the Government should “urgently” reconsider its legal case.

In the document, prepared on March 7, 2003, before it was clear the UN would not pass another resolution, Lord Goldsmith concluded: “I remain of the opinion that the safest legal course would be to secure the adoption of a further resolution to authorise the use of force.

“If we fail to achieve the adoption of a second resolution we would need to consider urgently at that stage the strength of our legal case in the light of the circumstances of at the time.” However, by the time British troops were sent in, Lord Goldsmith had told the Cabinet the war was legal even though no second resolution was obtained. In the document, Lord Goldsmith added that, in the light of the latest reporting by weapons inspectors, “you will need to consider very carefully whether the evidence of non-cooperation and non-compliance by Iraq is sufficiently compelling to justify the conclusion that Iraq has failed to take its final opportunity”.

Lord Goldsmith said it would be difficult to argue that an “unreasonable veto” by other Security Council members would entitle the Government to proceed with military action against Iraq. He concluded: “There are no grounds for arguing that an ‘unreasonable veto’ would entitle us to proceed on the basis of a presumed Security Council authorisation. In any event, if the majority of world opinion remains opposed to military action, it is likely to be difficult on the facts to categorise a French veto as ‘unreasonable’.”

Peter Brierley, whose son, Lance Corporal Shaun Brierley, was killed in Iraq aged 29 on March 30, 2003, said: “I can’t see that Tony Blair has any choice but to stand down, as he is damaging his party now,” he told Channel 4 News. “It seems to me that between the 7th and the 17th, there were a lot of changes to what (the Attorney- General) was actually saying.”

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