Some people have argued that UK involvement in the invasion of Iraq was partially or primarily aimed at securing its oil supplies, or at least aimed at supporting a US adminstration that had this aim. There is some evidence for this.
MI6 papers December 2002
The second of these papers discusses “how we could combine an objective of regime change in Baghdad with the need to protect important regional interest (sic) which would be at grave risk, if a bombing campaign against Iraq were launched in the short term” and sets out “a possible way ahead”.
A paragraph headed “Why move?” argues:
The removal of Saddam remains a prize because it could give new security to oil supplies[…]
In response to this paper, Simon McDonald, principal private secretary to foreign secretary Jack Straw, wrote to the chief of MI6/SIS
Thank you for your letter of 3 December, which the Secretary of State has read. He thought the two papers very perceptive and hopes that the Prime Minister reads them.
Oil industry meetings with ministers and officials before the Invasion
In 2011 a five documents were published in relation to a book and news story about Oil and Iraq. These are the minutes of meetings about Iraq between the UK government and oil companies BP and Shell, in the six months before the war.