Iran drops dollar from oil deals: report

"The dollar is an unreliable currency, considering its devaluation and the oil exporters' losses," he added.

The world's fourth largest oil exporter, Iran has massively reduced its dependence on the dollar over the past year in the face of US pressures on its financial system and the fall in the dollar.

Nozari did not specify in which currencies Iran was now being paid. In the past, officials have said most oil income was in euros, with a significant percentage in yen.

Japan, which purchases 20 percent of Iran's crude oil, has recently agreed to pay for the crude oil in yen, officials have said. The UAE dirham has also been mooted as a possible payment currency.

Iran has in the past months been whittling down the proportion of dollars in its oil revenue income. Officials in October said that dollars accounted for only 15 percent of payments and predicted the amount would fall to zero.