OPEC said its oil revenue plunged by $438billion to a 10-year low last year, as an increase in export volumes failed to compensate for the collapse in prices.
ISIS is making up for lost revenue from coalition strikes on its oil infrastructure by squeezing the population under its control through high taxes.
Scotland would be “entirely bankrupt” and probably “scuttling” for help had it secured independence, a business minister has claimed.
Nicola Sturgeon has faced calls to set up a Scottish version of the Office for Budget Responsibility as Labour said forecasts on oil revenues were out by 6,000%.
Watch our video interview with former UK energy minister Charles Hendry here.