Notably, the nation has dropped to fifth in the world for crude and condensate exports, down from its No. 3 spot a year ago, the US Energy Information Administration wrote in an updated country report published Friday.

Liquids production levels averaged 3.5 million barrels per day in 2012, down from 4.2 million barrels per day in 2011, the EIA said.

"In the last year in particular, Iran has seen a significant erosion in production capacity that is at least in part attributable to the sanctions," the agency said.

"Given