These ministers and officials have pointed to the instability of current oil sources - the Middle East, Caspian Region and Algeria - and the need for secure alternatives. Iraq has the second largest known oil reserves in the world.

"I can't say energy is irrelevant [to the Iraq conflict], but the issue is one we would have to deal with even if Saddam was a cuddly individual," a source in Britain's Foreign Office told the Guardian newspaper.

Last week, British Foreign Secretary Jack Straw told a gathering of British ambassadors in London that energy security was one of the top seven priorities of British foreign policy.