Iranian president Hassan Rouhani announced the discovery of a new oil field in southern Iran with over 50 billion barrels of crude oil. The discovery could potentially boost the country’s reserves by a third, according to the Associated Press. The announcement comes as Iran continues to struggle under crippling U.S. sanctions. “I am telling the White House that in the days when you sanctioned the sale of Iranian oil and pressured our nation, the country’s dear workers and engineers were able to discover 53 billion barrels of oil in a big field,” Rouhani said during speech in the desert city of Yazd. Once developed, the new oil field is set to become Iran’s second-largest after the Ahvaz field which contains 65 billion barrels of crude oil.