Iran claimed that it struck US military bases across the Middle East yesterday in response to American attacks on its southern border on Friday.

The tit-for-tat military strikes have once again disrupted shipping on the Strait of Hormuz and threaten to shatter the fragile peace deal.

A tanker on the Strait was struck by an 'unidentified projectile' yesterday, leaving the vessel damaged but the crew members uninjured, according to the United Kingdom Maritime Trade Operations.

The Panama-flagged crude tanker Kiku was reportedly carrying Qatari oil and was headed to the port of Fujairah in the United Arab Emirates.

Iran's Islamic Revolutionary Guards Corps said it targeted the American bases because it claims the US violated its own ceasefire deal.

Last night there were no reports of US facilities being hit. But earlier in the day, Bahrain, which hosts a US military base, reported drone attacks.

The Iranian reprisals came a day after the US attacked Iranian military facilities, including drone sites, around the Strait of Hormuz.

These came after Iran struck a cargo ship which it said was using an unauthorised route through the Strait on Thursday. 

The attack, which stopped all plans to evacuate thousands of sailors on the Strait, was described by Donald Trump as a 'foolish violation' of the truce.

The Joint Maritime Information Center yesterday raised the threat level in the Strait from 'moderate' to 'substantial'.