Explainer-What challenges could stand in the way of a final US-Iran deal?

The fate of Iran’s nuclear programme – which Trump cited as his main reason for going to war – may carry the greatest potential to unravel the talks.

WASHINGTON – When US and Iranian negotiators sit down in Switzerland on June 19 after nearly four months of war, the stakes could not be higher as they face an array of hurdles that could derail efforts to reach a comprehensive peace agreement.

While a breakthrough cannot be ruled out, most analysts are sceptical that the two sides can forge a final settlement within the 60-day window laid out in a “memorandum of understanding” that US President Donald Trump and Iranian leaders approved this week.

That interim pact kicked the hardest issues down the road to the next phase of negotiations, with no guarantee they will ever be resolved. The following are potential spoilers:

The fate of Iran’s nuclear programme – which Trump cited as his main reason for going to war – may carry the greatest potential to unravel the talks. Trump has already touted Iran’s commitment never to develop a nuclear weapon, but that largely restates long‑standing pledges by Tehran.

Where the negotiations could falter is over what to do with Iran’s stockpile of near-bomb-grade uranium. Trump has said he wants it shipped out or destroyed. Iran wants neither, though it has indicated a possible willingness to dilute the material.

Another sticking point is Iran’s future uranium enrichment. The US has at times demanded zero enrichment in Iran. Iran says it will not give up its right to enrich. Sources have said the two sides have previously discussed a potential moratorium of anywhere from 5 to 20 years, but compromise remains elusive.

Also in question is whether Iran will accept the level of international inspection conducted under the nuclear deal that former President Barack Obama reached in 2015 and which Trump ditched in 2018.

Questions remain about the strait, which Iran effectively blocked, triggering a global energy supply shock, after the US and Israel attacked on Feb 28. Under the MOU, the waterway, which normally carries one-fifth of the world’s oil, will be reopened on June 19, but shippers remain cautious.

The US says it will be toll-free. Iran, which gained leverage with control of the channel that it lacked pre-war, insists it will retain a management role.

Also standing in the way: Iran wants Trump to quickly lift sanctions and unlock billions in frozen funds, while the US says easing will be gradual and tied to Iranian compliance.

According to the text of the MOU read out by US officials on June 17, Iran would imme