November 8 2002: UN unanimously passes Resolution 1441, giving Iraq "a final opportunity to comply with its disarmament obligations" and warning of "serious consequences" if it did not. It takes its force from two earlier resolutions passed at the time of the first Gulf War

November 18 2002: Weapons inspectors led by Hans Blix return to Iraq for first time in four years

Over this period 250,000 US and British troops start to mass on Iraq's borders

January 27 2003: Mr Blix's first report is critical but not damning. It states: "Iraq appears not to have come to a genuine acceptance of the disarmament that was demanded"

Early February 2003: Britain and the US begin to argue for the Security Council to pass a further resolution authorising the use of force

February 5 2003: Colin Powell, the US Secretary of State, presents evidence to the Security Council that Iraq still has weapons of mass destruction

February 14 2003: Mr Blix says that Iraq's co-operation is improving. He voices doubts about key elements of the intelligence presented by Mr Powell.

February 28 2003: The Attorney General briefs No 10 policy advisers on the legal position. Mr Blair's office asks for his views to be put in writing

March 7 2003: Mr Blix tells the UN that Iraq has taken significant steps to comply with its disarmament obligations, but that questions remain. He asks for more time. Britain and US respond by setting a March 17 deadline for Saddam to comply

Lord Goldsmith sends Mr Blair his written legal advice setting out the case for and against the war. He says the legal case for war in 1441 is not clear, and warns that a second UN resolution explicitly authorising war would be the safest course.

If the UK failed to get a second resolution "we would need to consider urgently at that stage the strength of our legal case in the light of circumstances at the time". He does not however conclude that war would be illegal. This advice is not shown to Cabinet members

March 10 2003: Attempts to get a second UN resolution founder when French president Jacques Chirac says he will veto it because the inspection process has not had enough time

March 14 2003: Britain abandons its attempt to get a second resolution, citing the opposition of the French The British military and the Civil Service ask the Attorney General to "express a clear and simple view" on the legality of military action.

March 15 2003: The Attorney General writes to Mr Blair. In reply, he receives the written assurance that "it is indeed the Prime Minister's unequivocal view that Iraq is in further material breach of its obligations"

March 16 2003: President Bush and Mr Blair give the UN a 24-hour ultimatum to enforce its own demands for immediate Iraqi disarmament, or face war within days.

March 17 2003: The Attorney-General presents a revised, shorter version of his advice to Cabinet and later as a statement to Parliament. It expresses far fewer doubts than the earlier legal advice, and states unequivocally: "Authority to use force against Iraq exists from the combined effect of resolution 678, 687, and 1441."

March 18 2003: Mr Blair addresses Parliament, setting out the case for war

March 20 2003: Operation Iraqi Freedom begins at 2.45am Iraq time, with the bombardment of Baghdad

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