Washington: The US Senate unanimously approved a measure on Thursday to sanction the Central Bank of Iran, a move intended to shrink Iran's oil exports and deprive it of cash that might be used in nuclear or missile programmes.

The Senate measure would give the Obama administration power to bar foreign financial institutions that do business with the central bank from having correspondent bank accounts in the US.

If enacted, it could be much harder for foreign companies to pay for oil imports from Iran, the world's third largest exporter.

"The Central Bank of Iran has become a vital intermediary for purchasers of Iranian crude because existing sanctions against the Gulf country have constrained Iran's ability to access the international financial sector to settle oil trades," said Mark Dubowitz, director of the Iran Energy Project at the Foundation for Defence of Democracies in Washington.

The Obama administration opposed the amendment on the grounds that by targeting an important oil supplier for Asia and Europe, the move threatens to fracture the international coalition supporting coordinated pressure on Iran and may send oil prices soaring if world supply is perceived to be in jeopardy.

‘More money'

"There's absolutely a risk" that "the price of oil would go up, which would mean that Iran would, in fact, have more money to fuel its nuclear ambitions, not less," Undersecretary of State Wendy Sherman told the Senate Foreign Relations Committee on Thursday, before lawmakers voted.

Oil prices have increased 9.8 per cent this year to trade at $100.37 (Dh368) a barrel on the New York Mercantile Exchange yesterday.

The measure, sponsored by Senators Mark Kirk, an Illinois Republican, and Robert Menendez, a New Jersey Democrat, was an amendment to the 2012 defence authorisation bill, also passed yesterday, which sets Pentagon policy and spending targets. The House and Senate will need to negotiate a final bill that would go to President Barack Obama for his signature.

The aim of the sanctions, its sponsors said, is to deprive Iran of revenue and thereby force the regime to abandon nuclear-weapons work.

On November 8, a report by the United Nations International Atomic Energy Agency highlighted evidence of clandestine work, which Iran denied.