Slightly less than 10 percent of the drilling rigs currently in service in the world are operating in the Iranian oil and gas sector, a petroleum official said.

Rokneddin Javadi, a director at the state-owned National Iranian Oil Co. and deputy oil minister, was cited by the Oil Ministry's official news agency SHANA as stating that more than 140 rigs were in service in Iran. By his count, that's about 7 percent of the world total.

"The drilling industry of Iran is moving forward at an acceptable speed," the report read.

According to oilfield services company Baker Hughes, there were 1,918 rigs deployed worldwide as of January. The company offers no breakdown by country outside of North America, but noted about 20 percent of the rigs were deployed in Iran's part of the world.

Rig counts serve as a loose metric to gauge activity in exploration and production and a sign of general interest in a particular global sector. Rig counts are getting renewed attention as crude oil prices recover as they could indicate where investors are drawn. January's rig count was up about 8 percent from December and 1.4 percent higher year-on-year.

Iran is the only member of the Organization of Petroleum Exporting Countries with an allowance to increase oil production under a market-balancing scheme as it seeks to regain footing lost to nuclear-related sanctions. Several European energy companies from French supermajor Total to Austria's OMV have signed preliminary agreements to work with Iran in recent months.

Over the weekend, a separate report in Iranian news agency Tasnim reported newly found shale reserves in Iran's western province of Lorestan could hold up to 2 billion barrels of oil.

The report said exploration work is ongoing for the lighter grade of crude oil.

"The cost of conventional oil production in Iran stands below $10 per barrel, while shale oil production costs between $40 and $80 per barrel, making investment on shale oil economically infeasible at the current prices," the report stated.