Iranian Energy Minister Bijan Zangeneh said sanctions imposed in response to Iran's controversial nuclear research program means the Iranian economy is using more fuel oil than it would if South Pars were fully developed.
"Unfair sanctions against Iran have delayed the implementation of projects for gas production from the giant South Pars field," he said in a statement.
Iran in mid August said natural gas production during the first four months of the Iranian year, which begins March 21, was up 30 percent year-on-year.
South Pars accounts for about 35 percent of the total volume of gas produced from Iran. In the past, the government has held out the field's output as an option for Europe.
Zanganeh said in May his government was "always willing" to play a role in the European energy market, though European governments in the past have shied away from Iran because of lingering economic sanctions.