Iran's state radio says the country will shift its foreign currency reserves from the US dollar to the euro.
The report Monday said President Mahmoud Ahmadinejad had ordered to move on Sept. 12. It did not elaborate.
Iran has also been gradually moving to shift its foreign reserves to other currencies as the US looks to isolate Tehran over its controversial nuclear program.
Earlier this year, Iran said it was switching to the euro for its crude oil sales, which account for about 80 percent of its foreign income.
With 4.2 million barrels per day of crude output, Iran is OPEC's second largest exporter.
Iran's had about $54 billion in foreign reserves according to a Central Bank report for the third quart of 2008, the latest available.