In a statement late on Saturday, the Vienna-based International Atomic Energy Agency (IAEA) said the meeting was at the request of Russia, a key ally of Tehran.

Iran had made the same request in a letter to IAEA chief Rafael Grossi on Saturday following the strikes, which led to the death of Iran's supreme leader Ayatollah Ali Khamenei.

As a result, the agency will hold a "special session of the IAEA Board of Governors on matters related to military strikes of the United States and Israel against the territory of the Islamic Republic of Iran", the IAEA said in a statement.

That extraordinary meeting will precede an already scheduled session of the board, which represents 35 countries.

Following the strikes, the IAEA said it was "closely monitoring developments in the Middle East, and urges restraint to avoid any nuclear safety risks to people in the region".

The UN nuclear watchdog had also stressed on Friday the "utmost urgency" of its request to verify all nuclear material in Iran, according to a confidential report seen by AFP.

Western countries led by the United States and Israel, Iran's arch-enemy, accuse the Islamic republic of seeking to acquire nuclear weapons.

Tehran denies having such military ambitions, but insists on its right to this technology for civilian purposes.