The Iraq war was "illegal" and the idea that military action merely upheld UN Security Council resolutions was "absurd", the UN weapons inspector Hans Blix told the Chilcot inquiry yesterday afternoon.

Asked what he thought would have happened, had the March 2003 invasion not taken place, Blix said he would have completed the inspections and introduced proper monitoring of Iraq's nuclear, biological and chemical weapons capabilities. When pressed, he said that although he thought a diplomatic route could have been backed up by military threat, he doubted it would have involved the deployment of 250,000 men, and said the military pressure could have ensured that the inspections procedure was completed.

His own position on whether Iraq possessed WMDs at the time is rather more complex than is often thought: at the time of the "dodgy dossier" in September 2002, he said he personally expected the presence of weapons, but could not say so in his official capacity as an evidence-gatherer for the UN. He did also say at the time that he thought the dossier "plausible".

However, he changed his view in early 2003 when a scathing report produced greater Iraqi co-operation, with offers to excavate materials from the 1991 war and people involved in armament at that time offering to travel abroad for interviews. Blix says he communicated the change in his opinions to Tony Blair. He also insisted that his team was never denied access to sites, and that it was "not really" greeted by resistance or violence. If this had been the case, he said, he would have complained to the Security Council.

Despite this trend of increased co-operation throughtout the early part of 2003, Blix said he felt he could date the change in British attitude to 10 March 2003, shortly after he submitted a "working document" to the UN that Jack Straw described as "sensational", even though Blix himself felt that it provided very little new information.

Blix maintained that reports that Blair tried to get him to change his mind on the presence of WMDs in order to placate the US were false.

He felt that once his team began reporting back that no evidence had been found at any sites, the US and UK should have changed their policy -- that, he feels, is the main lesson that should be drawn from the situation. His only regret, he says, is the "harsh tones" he used in the January document, which consituted a warning to Iraq to improve co-operation, which it then did.

The issue of co-operation was the real revelation from Blix's evidence yesterday. He made it clear that the US and UK were moving towards military options despite an increased level of co-operation from the Iraqis and a lack of evidence found by the inspectors.