TEHERAN: Iran warned on Sunday that any new war with the United States could last longer than the previous conflict and that US President Donald Trump would not be the one to determine its duration.

"A potential future war could last longer than previous conflict, and the American president would not be in a position to dictate the timing or the conditions of its conclusion," said army spokesman Mohammad Akraminia, according to Iranian state television.

He was referring to the most intense phase of the fighting in the war that began on Feb 28 with US-Israeli strikes on Iran, killing the Islamic republic's supreme leader Ayatollah Ali Khamenei.

Iran responded by launching missiles and drones across the region, while the militant groups it backs also entered the fray in Lebanon and Yemen.