As stated in “The Report of the Iraq Inquiry – Executive Summary”: “203. Mr Blair told Cabinet on 6 March that the argument boiled down to the question of whether Saddam Hussein would ever voluntarily co-operate with the UN to disarm Iraq.
204. Mr Blair concluded that it was for the Security Council to determine whether Iraq was co-operating fully.
205. In his discussions with President Lagos on 6 March, Mr Blair stated that the US would go ahead without the UN if asked to delay military action until April or May.”

 – Commissioned by the Prime Minister The Right Honourable Gordon Brown MP, “The Report of the Iraq Inquiry: Executive Summary,” IraqInquiry.org.uk, March 6, 2003