A U.N. Security Council committee on Thursday imposed sanctions on two Iranian firms that violated a U.N. arms embargo on Tehran by shipping weapons to the Syrian government.

The move was welcomed by the United States. U.S. Ambassador to the United Nations Susan Rice said in a statement that the two firms blacklisted by the Iran sanctions committee were "significantly involved in Iranian arms smuggling, including smuggling to Syria."

"These companies - Yas Air and SAD Import Export Company - were responsible for shipping ammunition, assault rifles, machine guns, mortar shells and other arms from Iran to Syria," she said.