US President Donald Trump on Friday slammed Iran for carrying out a drone attack in the Strait of Hormuz, calling it a “foolish” violation of the ceasefire in the Middle East war.

“One of the Drones solidly hit the upper deck of a large and very expensive Cargo Carrying Ship” while three others were shot down, Trump posted on his Truth Social platform, in an apparent reference to an attack on a vessel the day before.

“Obviously, this is a foolish violation of our Ceasefire Agreement,” Trump added.

The British maritime security agency UKMTO announced on Thursday that a cargo ship in the strait was “hit on the starboard side by an unknown projectile, causing damage to the bridge,” but reported no casualties.

It said the incident occurred just 7.5 nautical miles (14 kilometres) off Oman’s coast.

The secretary general of the UN’s International Maritime Organisation, Arsenio Dominguez, then announced the suspension of efforts to evacuate some 600 ships and 11,000 sailors trapped in the Gulf by the war, which was launched by the US and Israel on February 28.

A ceasefire took effect on April 8, but sporadic violence has continued in the Gulf region, including attacks on ships by Tehran’s forces and US strikes on Iran.