The Supreme Leader also called on the country's Revolutionary Guards to mass-produce missiles.
The United States and its allies have said they are worried about Iran's missile program as they fear the weapons could carry nuclear warheads. Iran has long denied having any plans to develop atomic weapons.
"They expect us to limit our missile program while they constantly threaten Iran with military action. So this is a stupid, idiotic expectation," Khamenei was quoted as telling the IRNA news agency while on a visit to an aeronautics fair by the Revolutionary Guards.
"The revolutionary guards should definitely carry out their program and not be satisfied with the present level. They should mass produce. This is a main duty of all military officials," Khamenei said. REUTERS