ANALYSTS have long argued that a full Iranian shutdown of the Strait of Hormuz was improbable, largely because it would choke off Tehran’s own vital trade routes.

Yet Lloyd’s List Intelligence data shows that Tehran has pulled off the improbable.

Its sporadic attacks on vessels are deterring international shipping from transiting the chokepoint, but at least some of Iran’s own trade is getting through.

In the week March 16-22, 97% of all transits were made by Iran-linked vessels.

Last week was the busiest through the strait since the US and Israel first attacked Iran, with an estimated 48 cargo-carrying vessels above 48,000 dwt making the voyage.

More than 20% of those transits were by vessels with seemingly few links to Iran. Yet all transited via the lengthy and illogical Larak Island detour, which becomes much more logical when you know the Islamic Revolutionary Guard Corps uses it as a checkpoint to clear (or deny) vessels from transiting the strait.

Tehran is getting food in via bulk carriers, and some oil out too.

That’s not to say it’s plain sailing. Many of those bulkers had long waits outside the strait before getting the green light; some shadow fleet tankers reassessed their Iran calls and sought employment elsewhere.

Whether Iran can sell enough oil to prop up its beleaguered economy remains an open question. Nor should we expect a mad dash to join the queue at Checkpoint Larak any time soon.

But the movements add weight to Iran’s claims that the strait is open for business, but closed to its enemies. Vessels are transiting, and modestly increasing.

Iran helped the Houthis build a system that allowed favoured ships to pass through the Red Sea. The question now is whether it can replicate that in Hormuz, and for how long.

Joshua Minchin and Declan Bush
Senior reporters, Lloyd’s List

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