"Under current circumstances, the prices of oil will increase due to cold weather and also the psychological impact of foreign sanctions imposed on Iran's oil exports," said Mohammad Ali Khatibi, Mehr reported. 

Iran's Oil Ministry news service said on Monday, Iran now has 154.58 billion barrels of recoverable oil reserves and 33.69 trillion cubic meters of recoverable natural gas after finding significant quantities of both over the past year. 

According to the latest BP Statistical Review of World Energy 2011, Iran's proven oil reserves stood at 137.0 billion barrels of crude oil and gas condensate, plus 29.6 trillion cubic meters of natural gas, at the end of 2010. 

According to Iranian Oil Ministry website Shana, National Iranian Oil Company (NIOC) statistics show the country has added 833 million barrels of recoverable crude oil and gas condensates and 31.70 billion cubic feet (897 million cubic meters) of recoverable natural gas reserves since March last year. 

The reported increases in reserves would not change Iran's world rankings. It would remain in third place for oil behind Saudi Arabia and Venezuela and in second behind Russia for natural gas. 

Oil industry analysts have forecast Iranian oil output will fall by as much as 9 percent this year to an average of around 3.3 million barrels per day (bpd).

Meanwhile, oil prices moved above $101 a barrel Tuesday ahead of US crude supply figures that will provide clues about the strength of demand in the world's largest economy.

By early afternoon in Europe, benchmark crude for March delivery was up 55 cents at $101.46 a barrel in electronic trading on the New York Mercantile Exchange. The contract rose $2.24 to settle at $100.91 on Monday.

In London, Brent crude was up 13 cents at $118.06 a barrel on the ICE Futures exchange.

Oil has hovered near $100 for several months amid signs the US economy is improving. However, crude supplies have been rising, suggesting demand remains weak.