Not counting the contributions from oil, the Iranian economy grew 4.4 percent in the three months ending March 20, the government said.

The Iran Statistics Center said that, using fixed prices from 1997, gross domestic product increased both when including and excluding oil into accounts.

"Thanks to people's trust in their government and by forging a national unity, my administration managed to foster economic growth to 4.4 percent while the enemies tried to reduce oil prices to one third and one fourth," Iranian President Hassan Rouhani was quoted by the official Islamic Republic News Agency as saying.

Led by strong output from Saudi Arabia, an Iranian adversary, the International Energy Agency reported last week that crude oil production from all members of the Organization of Petroleum Exporting Countries was at a record level at the same time that demand was trending lower.

Iran is a member of OPEC. Total production for Iran in July was slightly above the previous month and its highest level at least since 2014.

Weak demand and higher oil production is part of the reason why crude oil prices are relatively unchanged from this date last year and more than 50 percent lower than this date in 2014.

Though sanctions relief means more Iranian oil on the market, the Iranian government has tried to make its economy less dependent on oil for revenue. Moody's Investor's Service found the Iranian economy is more diverse than other oil exporters in the region.

Rumors have circulated since late January that OPEC and non-member states may be considering production cuts or a freeze to drive up the price of oil. A proposal to freeze production at January levels collapsed when Iran said it would consider similar market control measures only after it regained the leverage it lost to sanctions.