The United States is set to overtake Saudi Arabia as the world's leading producer of petrol products for the first time since 1991.

US production levels have come level with output from Saudi at 11.5m barrels a day, according to the International Energy Agency.

The US development is down to advances in exploration technology which have made more US oil fields viable.

Since 2012 US oil output has increased by 3.5m barrels a day and is now on track to outstrip that of Saudi Arabia within the next two months.