Blair 'was warned invasion needed UN go-ahead'

A slew of newly declassified Government papers showed Lord Goldsmith, then the Attorney General, was initially "pessimistic" that there was sufficient legal basis for military action.

However, after being urged to change his view by the then foreign secretary Jack Straw – who warned against overly "dogmatic" legal advice – he eventually ruled it was lawful.

The inquiry heard how Mr Straw rejected the advice of his senior legal adviser at the Foreign Office, Sir Michael Wood, that an invasion without a UN Security Council resolution specifically authorising military action would be a "crime of aggression".

Sir Michael's deputy Elizabeth Wilmshurst, who resigned in protest on the eve of the invasion in March 2003, described the Government's treatment of the legal advice as "lamentable".

The inquiry also heard that No 10 had raised the prospect of going into Iraq without "international legal authority" for the use of force.

The extent of the concerns among Government lawyers will intensify the pressure on both Lord Goldsmith who gives evidence today, and Mr Blair, who appears on Friday.

Even while the negotiations were under way in October 2002 on Security Council resolution 1441 – which required Iraq to give up its supposed weapons of mass destruction – Sir Michael said he was being asked about the consequences of invading without legal authority. "This was a rather curious request and I am still not entirely sure what the purpose was," he said.

Following the passing of 1441 in November 2002, Lord Goldsmith expressed concern to Mr Straw that it was being seen in Government as the legal justification for military action.

Initially, Sir Michael said, it was made clear that he should not come down on one side or the other, but in January 2003 he took issue with Mr Straw over his assertion that it would still be possible to take action, even if they failed to get a second resolution authorising war.

"To use force without Security Council authority would amount to a crime of aggression," he wrote in a memorandum to Mr Straw.

Mr Straw replied: "I note your advice but I do not accept it."

In a letter to Lord Goldsmith dated February 6, Mr Straw argued for a legal interpretation "which coincides with our firm policy intention".

On March 7, Lord Goldsmith presented his opinion to Mr Blair in which he argued that a "reasonable case" could be made for legal action under 1441 although it would be safer to have a second resolution.

But with the diplomatic efforts to secure a resolution on the brink of collapse, on March 11 he was called to a meeting with Mr Blair, Mr Straw, defence secretary Geoff Hoon and chief of the defence staff Admiral Lord Boyce.

Two days later, his legal secretary David Brummell noted that he had come to a "better view" that a further resolution was not legally necessary.

Mr Brummell strongly denied any suggestion that Lord Goldsmith had been pressurised into giving the green light for war.

The inquiry continues.