A top Oil Ministry official says Iran, OPEC's second-largest producer, has completely stopped conducting all its oil transactions in US dollars.

Iran has dramatically reduced dependence on the dollar over the past year in the face of increasing US pressure on its financial system and the fall in the value of the American currency.

Oil is priced in US dollars on the world market and the currency's depreciation has concerned producers because it has contributed to rising crude prices and eroded the value of their dollar reserves.

Iran has already said it was shifting its oil sales out of the dollar into other currencies.

Oil Ministry official Hojjatollah Ghanimifard said Wednesday all oil transactions are now being carried out in euros and yen.