The quality of gasoline produced in Iran in an attempt to achieve self-sufficiency is well below global standards, a website quoted an official as saying, but his comments were rejected by the Islamic state's oil ministry.

The poor quality of Iranian gasoline was the main cause of pollution in the capital Tehran in recent weeks that forced the government to shut down offices, schools, and other organisations for days, say experts and some lawmakers.

"Our refineries have been designed to produce petrochemical products not gasoline," Aftab daily quoted lawmaker Qolamali Meygolinejad.
"A major part of Tehran's air pollution is due to the lack of standard in production of fuel in the country," said another lawmaker Mohammad Reza Rezaee, according to the daily.

Iran announced in September it had raised its gasoline output to attain self-sufficiency and foil sanctions imposed by the European Union and the United States targeting its energy needs. Tehran used to import up to 40 percent of its gasoline before it began producing it domestically.

"The standard defined by the Iranian Standard Organization for gasoline is Euro 4, but the gasoline produced inside the country does not comply with this standard," Fardanews quoted the head of the organisation Nezameddin Barzegari as saying.

"Experts have sampled the domestically produced gasoline and the results show that this gasoline is based on the Euro 2 standard with a 87% octane rating," he said, according to the website affiliated to conservative lawmaker Ahmad Tavakkoli.

The government's official website www.dolat.ir rejected Barezgari's comments and Iran's Oil Minister Massoud Mirkazemi has denied the poor quality of the strategic product, saying the gasoline produced at the country's refineries is "comparable with world standards."

Iran is the world's fourth-largest oil exporter and sits on the second-largest gas reserves after Russia, but a lack of refining capacity and sanctions hindering access to foreign capital and know-how have forced the country to import gasoline.