18 March 2003 Parliamentary Approval for the invasion of Iraq

British Parliamentary approval for the invasion of Iraq was given by the elected members of the British House of Commons to Tony Blair's government on the eve of the 2003 invasion of Iraq, in a series of two votes, on 18 March 2003.

There is no constitutional requirement for the government to seek any explicit form of Parliamentary approval before committing British forces to military action. The Royal Prerogative permits the government, in the Sovereign's name, to give the order to begin military action.

However the political controversy over whether to participate in military action, which covered the legal legitimacy as well as foreign policy questions, had been under discussion for many years. As early as 1999, the anti-war MP Tam Dalyell had proposed a Ten Minute Rule Bill called Military Action Against Iraq (Parliamentary Approval) Bill to "require the prior approval, by a simple majority of the House of Commons, of military action by British forces against Iraq." Dalyell was given leave to bring in his Bill [1], but it could not be debated and voted upon because as a Bill that affected the Royal Prerogative, the consent of The Queen was needed before it could be debated in Parliament (known as Queen's Consent). The Government advised Queen Elizabeth II to refuse to grant consent, which she did, as constitutional convention requires.

The deployments of UK forces to Saudi Arabia and Kuwait, along with forces of the United States, were a clear preliminary to military action. Several debates were held on UK policy on Iraq. Finally, on 17 March 2003, US President Bush gave an ultimatum to Saddam Hussein to give up power within 48 hours or face military conflict. Previous votes had endorsed government policy of confronting Iraq through the UN.

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