June 27 (Bloomberg) -- Iranians rioted in the streets of Tehran after the government imposed rationing of gasoline, which the country spends $5 billion a year to import.

Starting today, drivers will be allowed 100 liters, or about 26 gallons, of gasoline a month, Oil Minister Kazem Vaziri-Hamaneh said on state television. Taxis will get 800 liters. Lawmakers said earlier this month drivers would probably get five or six liters a day, 50 percent more than the program actually grants them.

``At least'' five filling stations in Tehran were burned and damaged following the announcement, Nasser Raissi-Far, the head of Tehran province's filling station union, told state-run Mehr news.

Although Iran holds the world's second-biggest energy reserves, it imports more than 40 percent of the gasoline it uses. Demand is buoyed by subsidies while supply is restricted by waste and lack of refinery capacity. Service stations in Iran sell the fuel at 1,000 Iranian rials a liter, about 42 U.S. cents a gallon.

The dependence on imports makes Iran vulnerable to United Nations economic sanctions, which are likely to increase in coming months if it refuses to suspend uranium enrichment. Since December, the UN Security Council has limited the transfer of nuclear technology and the international travel of some Iranian officials.

Parliament Summons Minister

Iranian lawmakers have summoned Vaziri-Hamaneh to come to parliament today to ``answer questions'' on the rationing, Iranian Labor News Agency reported, without elaborating. Iran has been trying for more than a year to ration gasoline, and the latest indication it gave was that the program would start on July 23.

The rationing plan is set to last four months and may be extended, a spokesman for the oil ministry who declined to be identified said in a telephone interview. Drivers will be allowed to buy their daily gasoline allocation up to four months in advance, Vaziri-Hamaneh said on state television.

Parliament still must decide whether drivers will be allowed to buy gasoline above their quota if they pay market prices, the oil ministry's press agency, Shana, said on its Web site today.

The second-biggest oil producer in the Organization of Petroleum Exporting Countries spends about 52 U.S. cents to import a liter of gasoline, Hojatollah Ghanimifard, National Iranian Oil Co.'s executive director for international affairs, said yesterday.

Domestic consumption of gasoline has increased 10 percent a year on average over the past five years, according to the International Monetary Fund. Iran won't have oil to export by 2019 if consumption keeps growing at the same pace, Seyed Mohsen Yahyavi, the deputy chairman of Iran's parliamentary energy commission, said last November.

Relying on Cars

Tehran is one of the more populous cities in the world, with an estimated 14 million inhabitants, who rely on cars to move around. Public transport is underdeveloped compared with other major cities, with just two subway lines operating so far.

The Pakyan car, a descendant of Britain's Hillman Hunter owned by four out of 10 Iranians, uses as much as 16 liters of gasoline per 100 kilometers, about 15 miles per gallon. The 3.3-liter-a-day ration limits the least efficient Pakyans to about 20 kilometers, or 12 miles, a day. That's not enough to get from central Tehran to the city's new airport, 35 kilometers to the south.

Nissan Motor Co.'s Patrol model, the most common four-wheel- drive vehicle in Iran, uses more than 25 liters per 100 kilometers.

Rationing probably will make smuggling more difficult. Smugglers had taken advantage of the difference with market prices to export gasoline to neighboring Afghanistan, Pakistan, Iraq and Turkey, illegally drawing $1 billion in subsidies from the government each year, Iranian oil officials said.

The program is also likely to create a parallel market. Smart cards used to record how much gasoline people buy are already being sold on the black market, the newspaper Sarmayeh reported May 22.

To contact the reporter on this story: Marc Wolfensberger in Tehran at mwolfens@bloomberg.net.

Last Updated: June 27, 2007 06:09 EDT