WASHINGTON: U.S. officials are committed to taking steps to freeze the assets of the Iranian central bank and to working with U.S. allies to do the same, a senior U.S. Treasury official said Thursday.

"We are committed to taking action against the CBI (Central Bank of Iran) to freeze its assets, to work with our allies to have them take a similar action, and to work with our allies to encourage them to take the steps that they have already indicated a willingness to consider, which is to ramp down their involvement with the CBI and their purchases of Iranian oil," Under Secretary of Treasury for Terrorism and Financial Intelligence David Cohen told U.S. lawmakers.