An Iranian soldier stands guard near Iranian
An Iranian soldier stands guard near IranianReuters

Iran launched massive air defense drills across half the country on Monday, warning it would act against aggressors less than a week after Washington accused Iranian warplanes of firing on a U.S. drone.

Code-named "Modafe'an-e Aseman-e Velayat 4 (Defenders of Velayat Skies 4)", the drills will take place this week across 850,000 square kilometers (330,000 square miles) of Iran's northeast, east, and southeast regions, Iranian media reported.

Radar air defense and missile systems as well as tapping, artillery and surveillance systems will be employed during the first stage of the exercises, Fars News Agency reported.

Different units of the Iranian armed forces, including the Islamic Republic of Iran Air Force (IRIAF), aerospace forces of the Islamic Revolution Guards Corps (IRGC), airborne units of the Army Ground Force and the Navy as well as the Basij (volunteer) force and the Iranian border guard units will participate in the annual air defense war-game, Fars quoted the spokesman for the exercises, Shahrokh Shahram, as saying.

The 'Velayat-4' maneuvers will involve the biggest air drills the country has ever held, Press TV reported.

"These drills convey a message of peace and security to regional countries," Shahram said. "At the same time they send out a strong warning to those threatening Iran."

The operating units will exercise defending hypothetical sensitive site, he added.

In addition to testing mobility and rapid reaction capability of participating units, the air defense units will test artillery and missile systems' capabilities for confronting different types of Unmanned Aerial Vehicles (UAVs) flying in different altitudes, according to Fars.

Last week, the U.S. Pentagon said Iranian planes opened fire on an unarmed U.S. drone over international waters on November 1.

Iran responded by saying it had repelled "an enemy's unmanned aircraft" violating its airspace. Neither Israel nor the United States have ruled out military action against Iran if diplomacy fails to halt its nuclear weapons program.