State Department spokesman Adam Ereli said U.S. officials are planning to discuss American objections to the sale with their Russian counterparts.
Russian Defense Minister Sergei Ivanov confirmed on 5 December that Moscow had signed a deal with Tehran for the delivery to Iran of arms including short-range surface-to-air Tor-M1 missile systems, which are capable of shooting down both aircraft and incoming missiles at low altitudes.
Ivanov called the systems defensive weaponry and said they will not change the balance of forces in the region.
(Reuters/AP/dpa)