Foreign Ministry Spokesman Ramin Mehmanparast said U.N. Resolution 1929 was itself illegal and, therefore, was not legal grounds for the abrupt cancellation of the deal for Russian-made anti-aircraft missile systems.
Mehmanparast also said at his weekly news briefing that Moscow's "long-term interests will not be realized by getting engaged in U.S.-sponsored games" against Iran, Press TV reported.
Russian President Dmitry Medvedev last week pulled the plug on the sale, which had been agreed to in 2005. He said Resolution 1929, which prohibits military sales to Iran, justified the cancellation.
Iran contends that the resolution does not cover defensive weapons such as the S-300 air defense system.
Another Iranian official said over the weekend that Tehran should take legal action against Moscow.
The Tehran Times said Tuesday that Medvedev's decision has prompted increased interest among Iranian experts in designing an Iranian-made air defense system.