The US navy’s fifth fleet said it was assisting the tankers, which issued distress calls near the strategic Strait of Hormuz.

Reports of the explosions originally came from the same Hezbollah-linked news agencies in Lebanon that correctly reported attacks on tankers docked off the coast of the UAE in May. The US blamed those attacks on Iran – an accusation Tehran has denied.

The suspected attacks occurred on one of the world’s busiest oil routes, and the price of oil surged as the initial reports emerged.

Front Altair was carrying 75,000 tonnes of naphtha, a petrochemical feedstock, when it was “suspected of being hit by a torpedo”, said Wu I-Fang from Taiwan’s state oil refiner CPC, which chartered the tanker. Iran state media reported that the Front Altair had sunk, though the ship’s operator, Frontline, said this was not the case.