Update: An Iranian military official described the encounter as "decisive" action by Iran: "Iran will use all its capabilities, including the relevant international agencies, to follow up on this case," Maj. Gen. Ahmad Vahidi said Friday, according to Iran's semi-official news agency ISNA.

Original story: Iran said Friday it would confront any effort to transgress its airspace, responding for the first time to accusations that two of its warplanes opened fire on a U.S. Air Force drone over international waters,

“The Iranian armed forces will respond decisively to any act of transgression,” Major General Seyed Masoud Jazaeri said Friday, in response to the CNN report that two Iranian jets fired on an unmanned American drone over the Persian Gulf. "If any foreign planes try to enter our country's space, our armed forces will confront it," he was quoted as saying, according to Fars News.

The statement, which neither confirms or denies the encounter, comes a day after Security Clearance first reported the incident - later publicly confirmed by the Pentagon. The incident triggered a formal warning by the United States to Iran through diplomatic channels amidst concerns it will further heightens tensions between the two countries over Tehran's nuclear program.

Also: Iran's nuclear ambitions to challenge Obama in second term

The warning came after the disclosure that two Iranian Su-25 fighter jets fired on an unarmed Predator drone conducting routine surveillance in international airspace east of Kuwait, 16 miles off the coast of Iran, Pentagon Press Secretary George Little told reporters Thursday the drone was not in Iran's territory.

"Our aircraft was never in Iranian airspace. It was always flying in international air space. The recognized limit is 12 nautical miles off the coast and we never entered the 12 nautical mile limit," Pentagon Press Secretary George Little said in responding to questions from reporters after CNN reported the incident.

The Predator drone was not hit in the November 1 incident, and it returned under its own power to its base, he said.