The US Treasury’s top official fighting the financing of terrorism said on Thursday that Washington was considering additional sanctions on Iran’s central bank

WASHINGTON - The US Treasury’s top official fighting the financing of terrorism said on Thursday that Washington was considering additional sanctions on Iran’s central bank to further isolate the country financially.

In testimony prepared for delivery to the Senate Banking Committee, Treasury Undersecretary David Cohen said the Obama administration’s efforts to tighten the financial and commercial screws on Iran were paying off, but other approaches were also being considered.

“I can assure the committee, as Secretary (Timothy) Geithner said in his letter of August 29, ‘All options to increase the financial pressure on Iran are on the table, including the possibility of imposing additional sanctions against’” Iran’s central bank.

Iran faces US and international sanctions over its nuclear program. Iran says its nuclear work is peaceful and aimed at generating electricity.

US authorities said on Tuesday they had uncovered a plot by two men linked to Iran’s security agencies to hire a hitman to kill Saudi Arabia’s Ambassador to the United States Adel al-Jubeir with a bomb planted in a restaurant. One man, Manssor Arbabsiar, was arrested last month while the other was believed to be in Iran.

Cohen called that allegation “a dramatic reminder that the urgent and serious threat we face from Iran is not limited to Iran’s nuclear ambitions.”

Although US financial institutions are already generally prohibited from doing business with any bank in Iran, including the CBI, Cohen said further US action against the Iranian central bank, if it had international support, could further isolate the institution.

The United States has pressed hard for governments and companies to stop dealing with Iran and sanctions on the financial sector have made it harder to trade.