Iran will attack any country whose territory is used by "enemies" to launch a military strike against its soil, the deputy head of Iran's elite Revolutionary Guards told the semi-official Fars news agency on Sunday.
"Any spot used by the enemy for hostile operations against Iran will be subjected to retaliatory aggression by our armed forces," Hossein Salami said during military manoeuvres.
The Revolutionary Guards began the two-day ground exercises on Saturday as a show of military might as tension rises between Tehran and the West over Iran's disputed nuclear programme. Iranian media called it a small-scale exercise in southern Iran.
The United States and Israel, Iran's arch-enemies, have not ruled out a military strike on Tehran if diplomacy fails to resolve the nuclear standoff. Iran says its nuclear programme is purely peaceful, not aimed at developing weapons.
Salami did not identify which countries he meant as possible launching pads for military action against it.
The six, US-allied Gulf Arab states in the Gulf Cooperation Council have said they would not allow their territories to be used for attacks on Iran.
But analysts say that if Iran retaliated for an attack launched from outside the region by targeting US facilities in Gulf Arab states, Washington might pressure the host nations to permit those bases to hit back, arguing they should have the right to defend themselves. The Gulf states that host US military facilities are Qatar, Bahrain and Kuwait.
Iran has warned that its response to any such strike will be "painful", threatening to target Israel and US bases in the Gulf, along with closing the vital Gulf oil shipping route through the Strait of Hormuz.