The U.S. Senate has approved new sanctions on trade with Iran's energy, port, shipping, and ship-building sectors.
The Senate voted 94-0 on November 30 to make the new sanctions part of an annual defense-policy bill.
The United States has imposed a series of sanctions on Iran that are aimed at pressuring the Islamic republic into halting its nuclear development program.
Iran's currency has plunged this year as its oil exports were slashed by U.S. and European sanctions.
The bill still needs to be approved by the House of Representatives and signed by President Barack Obama before it becomes law.
Iran says its nuclear program is for peaceful purposes.
Based on reporting by Reuters and AFP