Two people were injured by two Iranian drones that struck the exclave of Nakhichevan in Azerbaijan on Thursday, Baku said, summoning the Iranian ambassador and stating that this attack would not go "unanswered".

"A drone struck the terminal at the airport in the Autonomous Republic of Nakhichevan, while another drone fell near a school building in the village of Chakarabad," the Foreign Ministry said in a statement.

"We strongly condemn these drone attacks launched from the Islamic Republic of Iran which damaged the airport building and injured two civilians," he added.

The exclave of Nakhichevan borders Iran and is separated from the rest of Azerbaijan by Armenia.

A video published by the Azerbaijani agency APA, not verified by AFP, shows a drone crashing near the airport's entrance building, causing an explosion.

Azerbaijani diplomacy stated that it had summoned the Iranian ambassador to express its "strong protest" against the attack, which "violates the norms and principles of international law and contributes to the escalation of tensions in the region."

"Azerbaijan reserves the right to respond with appropriate measures," she said.

The Azerbaijani Ministry of Defense, for its part, indicated that Baku "is preparing the necessary retaliation to protect the territorial integrity and sovereignty of our country, in order to ensure the safety of civilians and civilian infrastructure," adding that "these belligerent acts will not go unanswered.

Tehran has long expressed concern that Israel, a close ally of Azerbaijan and a major arms supplier, is using the territory of this former Soviet republic in the Caucasus, located northwest of Iran, to launch attacks against its territory.

Last June, Baku stated that it would "never" allow its territory to be used to launch attacks against Iran, which was then the target of a vast Israeli offensive.