Abbas Araghchi, the former Iranian envoy to Japan, said from Geneva, Switzerland, negotiations could open the door for an energy sector that has been handicapped by sanctions.
"As a result of negotiations [with the five permanent members of the U.N. Security Council and Germany], we hope that we can conclude these negotiations so that the negotiations with Japan would expand much better than before," he said in an interview with the Japanese newspaper Yomiuri Shimbun published Monday.
The newspaper said Iranian exports dropped from 560,000 barrels of crude oil per day in 2006 to 120,000 bpd in June because of sanctions imposed on Iran's energy sector.
Western sanctions on Iran are designed to starve the government of energy revenue it could use to finance a nuclear program that adversaries fear is geared toward weapons.
Two days of multilateral talks in Geneva on Iran's nuclear program were described jointly by Iranian Foreign Minister Javad Zarif and European Union foreign policy chief Catherine Ashton as "substantive."