Ayatollah Ali Khamenei was speaking two days after the United Nations atomic agency released a report that for the first time said Iran was conducting experiments whose sole purpose was the development of nuclear arms.

"The enemies, particularly the United States and its pawns and the Zionist regime, should know that the Iranian nation does not seek to invade any country or nation," he said, addressing officers at a military academy in Tehran.

"But Iran will strongly respond to any invasion or attack with such power and in a way that the aggressors and invaders will be smashed from the inside. Anybody who takes up the idea of an attack on Iran, should get ready to receive a strong slap and an iron fist."