A growing number of lawmakers are calling for the United States to consider military action against Iran to prevent Tehran from acquiring nuclear weapons.
Defense Secretary Leon Panetta has said that all options are on the table, but the White House insists Obama is committed to using sanctions to pressure Iran.
Iran, however, has threatened to close the Strait of Hormuz, and on Friday said it would stop selling oil to Britain and France after the European Union imposed new sanctions.
Last week, Israeli officials blamed Iran for organizing a series of attacks targeting diplomats in Georgia and India. Iran has denied responsibility.