New Delhi, April 8 -- Shipowners are rushing to understand the fine print of a US-Iran ceasefire that could temporarily unblock the Strait of Hormuz and open an exit for more than 800 vessels trapped in the Persian Gulf.

The vital waterway has been virtually closed since US and Israeli strikes at the end of February prompted Iran to tighten its control, triggering an unprecedented energy-supply crunch. Unable to guarantee the safety of thousands of seafarers and their cargoes, vessels have instead been loitering on either side, and traffic has slowed to a trickle.

Then, hours before a deadline set by President Donald Trump ran out during the US evening on Tuesday, the two sides agreed a ceasefire in exchange for a reopening.

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