Obama signed an executive order Monday authorizing the State and Treasury departments to impose sanctions on foreign financial institutions that are involved in the purchase or sale of the Iranian rial, the nation's currency.
The Treasury Department in February tightened sanctions in a way that it said would restrict Iran's ability to use oil revenue that may be held in foreign banks.
The rial collapsed last year from sanctions pressure. White House spokesman Jay Carney said the rial lost half its value since early 2012. This is the first time U.S. measures have targeted trade in the rial.
Rules that go into force July 1 also target the sale of goods and services linked to Iran's automotive sector.
Economic sanctions on Iran are intended to starve the government of revenue needed to finance its controversial nuclear program. A U.N. report this week said there were ongoing concerns about the intent of Iran's nuclear activity.
"If the Iranian government continues down its current path, there should be no doubt that the United States and our partners will continue to impose increasing consequences," Carney said in a statement.
Existing sanctions on Iran prompted the Iranian government to search for ways to rely less on oil revenue.