Iran is to assume the presidency of OPEC for the first time in 36 years.
Oil minister Masoud Mir-Kazemi was elected as president of the Organization of Petroleum Exporting Countries at a one-day meeting of the group, which comprises 12 oil-producing states.
He will hold the presidency from 1 January 2011.
Iran is OPEC's second-largest oil producer and holds about 10% of world oil reserves.
At the meeting in Vienna, OPEC also agreed to keep its oil production target unchanged at 24.8 million barrels a day.
The price of oil is trading at $US84 a barrel.