As weapons inspectors return to Baghdad after a four-year absence, BBC News Online examines key moments in their chequered relationship with Iraq's leadership.
28 February 1991: Gulf War ends, leaving Iraq subject to UN sanctions and arms inspections.
29 October 1997: Iraq bars US weapons inspectors, provoking a diplomatic crisis which is defused with a Russian-brokered compromise.
13 January 1998: Iraq blocks an inspection by a US-dominated team and accuses its leader, Scott Ritter, of spying for America.
23 February 1998: UN Secretary General Kofi Annan announces a deal on weapons inspections after meeting Saddam Hussein in Baghdad.
31 October 1998: The Iraqi leadership says it has ceased all co-operation with Unscom, the United Nations Special Commission set up for weapons inspections in Iraq.
14 November 1998: Baghdad tells the UN it is willing to allow inspections to resume.
17 November 1998: Unscom inspectors return to Iraq.
16 December 1998: The UN orders weapons inspectors out of the country after Unscom chief Richard Butler issued a report saying the Iraqis were still refusing to co-operate. US air strikes on Iraq begin hours later.
17 December 1999: Unscom is replaced by the UN Monitoring, Verification and Inspection Commission (Unmovic). Iraq rejects the resolution.
1 March 2000: Hans Blix assumes the post of Unmovic executive chairman.
3 May 2002: Unmovic and Iraqi officials hold talks - Mr Annan says they are the first to take place at technical level since December 1998.
5 July 2002: UN-Iraq talks end without agreement on inspections as Baghdad seeks assurances that sanctions will be lifted.
31 July 2002: Richard Butler tells a US Senate committee that Iraq stepped up the production of chemical and biological weapons after UN inspections ended - and might even be close to developing a nuclear bomb.
1 August 2002: Iraq says the chief weapons inspector, Hans Blix, is welcome in Baghdad for "technical talks".
12 September 2002: President Bush addresses the UN General Assembly and warns Iraq that military action will be unavoidable if it does not comply with UN resolutions on disarmament.
16 September 2002: UN Secretary General Kofi Annan says he has received a letter from the Iraqi Government offering to allow the unconditional return of weapons inspectors.
24 September 2002: Britain publishes a report on Iraq's weapons programmes.
28 September 2002: Iraq rejects a draft UN resolution proposed by the United States for with strict new rules for weapons inspections.
1 October 2002: Hans Blix and Iraq agree practical arrangements for the return of weapons inspectors. US Secretary of State Colin Powell rejects it and says the US wants a tough new UN Security Council resolution.
11 October 2002: The US Senate follows the House of Representatives in authorising President Bush to use force against Iraq.
15 October 2002: Saddam Hussein wins 100% of the vote in a referendum on a new presidential term for him.
25 October 2002: US formally proposes a new resolution on disarming Iraq to the UN Security Council.
4 November 2002: Saddam Hussein says Iraq will comply with a new UN resolution as long as it does not serve as an excuse for US military action.
8 November 2002: UN Security Council unanimously passes a new resolution on Iraq's disarmament, warning of "serious consequences" for material breaches.
12 November 2002: Iraq's parliament rejects the UN resolution.
13 November 2002 Iraq's Government accepts the UN resolution.
18 November 2002: Hans Blix leads UN inspectors back to Baghdad to start their mission.
http://news.bbc.co.uk/2/hi/middle_east/2167933.stm