"We think it was done by Iran. Because they are very inaccurate, as you know, with their munitions. They have no accuracy whatsoever," Trump told reporters aboard Air Force One.

According to Iranian authorities, a strike hit a girls' elementary school last Saturday, killing more than 150 people, mostly students.

Israel and the United States have not claimed responsibility for the reported attack -- with US officials saying it remains under investigation -- while Iran has blamed Washington for the strike.

AFP has neither been able to access the site in order to verify the incident, nor to obtain independent confirmation of a toll.

Iran's Revolutionary Guards said Friday they had targeted a US base in the UAE that they alleged had been used as a launchpad for the strike.

"Al-Dhafra air base, belonging to American terrorists in the region, was targeted using drones and precision missiles," the Guards said in a statement broadcast on state TV.

The Pentagon has confirmed it is investigating, while Secretary of State Marco Rubio has said the US would "not deliberately target a school."

The New York Times newspaper reported Thursday that US military statements indicating forces were attacking naval targets near the Strait of Hormuz, where a Revolutionary Guards' base is located, "suggest they were most likely to have carried out the strike."

An analysis of social media posts from the time of the attack, as well as photos and videos from witnesses, indicated that the school had been struck at the same time as Guards' naval base sites, the Times said.