Exactly two years ago this month, a cheerful gathering of Iraqi and US officials waved goodbye to the tanker Ottoman Dignity as it departed from the Turkish port of Ceyhan, carrying the first barrels of oil to leave Iraq since the US invasion.

After praying and turning on the valves to load the oil on to the tanker, Mohammed al-Jibouri, Iraqi's top oil official at the time, said: "We hope we're going to pump more and more with this export."