Trump heralds Iran deal but questions - and risks - remain

The announcement of a deal to end hostilities between the US and Iran has provided Donald Trump with a very welcome birthday present – although it's wrapped in a fair measure of uncertainty.

In his social media post heralding the agreement, the American president said that the Strait of Hormuz would be open to commercial shipping and the US would lift its naval blockade.

"Let the oil flow!" Trump exclaimed on Sunday.

He went on to declare that, in contrast with the failures of past American presidents, he secured a "great deal" that would bring "peace and security to the whole region".

Such hyperbole is nothing new for Trump, of course. His declarations about last year's agreement ending the Gaza War – "a peace for all eternity" and the "beginning of the age of faith and hope and of God" - were equally sweeping, even as the reality on the ground has fallen far short.

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In such high-stakes diplomatic agreements, success or failure usually hinges on the details. And here, the details are scarce.

In a Sunday evening interview with Fox News, Vice-President JD Vance said that Iran never possessing a nuclear weapon was "built into this agreement" and that the US will be able to verify compliance.

Yet questions remain over crucial issues including what the restrictions on enrichment will be and what should happen to the stockpile of highly enriched uranium Iran has now.

Some of this is sure to be worked out in subsequent negotiations and "technical" talks conducted during a 60-day extension of the current ceasefire. But if anything is clear after decades of efforts to cajole and coerce Iran into giving up its nuclear ambitions, it's that there are no guarantees, no matter what the US believes is secured in this "memorandum of understanding".

As if to underscore this point, Iran's Supreme National Security Council released a statement on Sunday that "final negotiations will be postponed until after the implementation of the other party's commitments under the memorandum".

What those commitments are - and how Iran interprets them - will help determine whether this deal sticks.

Energy market experts warned that moving of oil through the strait is unlikely to immediately return to pre-war levels. Clearing a large backlog of tankers, removing mines, and restoring regular oil shipping and production could take weeks.

With several days to go before the official signing, Iran and the US have time to settle key details to ensure the deal's success - but there's also time for it to fall apart.