The U.S. has concluded that nearly half of Iran's monthly earnings from crude oil exports are accumulating in accounts overseas because of sanctions that restrict Tehran's access to the money.
The estimates, provided to The Associated Press by a senior U.S. official and never released before, are the latest indication that new sanctions imposed in February are deepening Iran's economic distress and making it increasingly difficult to access billions of dollars in vital oil revenues. The official spoke on condition of anonymity because of the sensitivity of sanctions policy.
The U.S. hopes the pressure will force Iran to compromise on its nuclear program, which the West suspects is aimed at making a weapon. Iran insists it is for peaceful purposes only and has not budged on demands to halt uranium enrichment, a process that can be used to make fuel for energy production or for a nuclear weapon.
Still, analysts say Iran's economy has proved resilient and flexible enough to offset some sanctions damage. The country has diversified its exports and become less reliant on sanctioned oil.
Mark Dubowitz, director of the Foundation for Defense of Democracies and an advocate of tougher sanctions, said at the current trajectory Iran can continue to muddle through economically for a few more years. And some experts have concluded Iran could produce enough material to build a nuclear weapon by mid-2014.
"Without massively intensified economic pressure and a real threat of military force ... Iranian nuclear physics will continue to outpace Western economic pressure and diplomacy," Dubowitz said.