It may take days for the United States and Iran to agree terms to end the war but the shape of the deal is clear. And Iranian negotiators appear to have won some important concessions.On the brink of peace?Hours after Donald Trump said an agreement with Iran had been “largely negotiated”, a message repeated in an official White House communication, the US president said on Sunday that he was in no hurry to do the deal. A US official briefed reporters that it could be days before the memorandum of understanding is published, suggesting that the delay was caused by the slow and opaque nature of Iran’s decision-making process.“There is still back and forth on specific details. Some words we care about, Some words they care about,” Axios quoted the official as saying.“Our understanding is that the supreme leader, Mojtaba Khamenei, has endorsed the broad template of the deal. Whether this becomes an agreement is still an open question.”Iran’s foreign ministry spokesman Esmaeil Baqaei described the memorandum of understanding as “a kind of framework agreement” before a final deal is reached within 30 to 60 days. It would see the Strait of Hormuz gradually reopened to shipping with no toll charged and the US lifting its blockade of Iranian ports.Iran’s Tasnim news agency reported that the US would suspend sanctions on Iranian oil and petrochemical products during the negotiating period, which would also see the gradual unfreezing of an estimated $100 billion (€85.9bn) in frozen assets held overseas. Tehran wants some of the assets to be unfrozen immediately before what the US describes as a gradual unfreezing linked to Iranian concessions on uranium enrichment and nuclear material.“No dust, no dollars. If no highly enriched uranium is given, they will get no relief,” the US official said.“The more they do, the more they get. There will be no immediate unfreezing of funds.”Baqaei said the nuclear issue was not part of the initial framework but would be “subject to separate discussions” at a later date. Iran’s Fars news agency said that Iran had made no commitment “to hand over nuclear stockpiles, remove equipment, shut down facilities or even commit not to build a nuclear bomb” as part of the framework agreement.The US side says an Iranian commitment to give up its stockpile of highly enriched uranium was a key element of the agreement, although the details of how it would do so would be discussed in a later round of negotiations. These positions may not be as irreconcilable as they appear because in the draft agreement negotiated by Oman before the US attacked Iran on February 28th, Tehran agreed to “zero stockpiling”.The mechanism proposed was that, instead of being sent abroad, the highly enriched uranium would be downblended to the lowest level possible and converted into fuel. This would have been implemented under verification by the International Atomic Energy Agency.Under the framework agreement, the war between Israel and Hizbullah would end, and although Binyamin Netanyahu was cut out of the negotiations, Trump said the Israeli prime minister will “do whatever I want”. This remark may have been designed to reassure Iran while also offering Netanyahu political cover by making clear to the Israeli public the US president’s determination to force through the deal.Trump’s agreement to postpone negotiations on the nuclear issue, beyond a broad commitment on enrichment in the framework agreement, represents an important concession to Tehran on the sequencing of talks. The US has until now insisted that the nuclear issue must be part of the opening stage of negotiations, fearing that Iran will pocket any gains from the next 60 days of talks and slow-walk the nuclear talks.The issue of sequencing was a crucial element of the Brexit negotiations, when Britain wanted the divorce arrangements and the trade agreement to be conducted concurrently. The European Union insisted that Britain should first agree the divorce terms, including arrangements for Northern Ireland, before any talks would begin on the trade agreement.When one side in a negotiate prevails over the sequencing of talks, it often gains an advantage in terms of maintaining leverage or denying it to the other side. This was true in the Brexit negotiations, when Britain was unable to use Ireland as a hostage in the talks and the trade deal that was agreed was broadly on the EU’s terms.Trump decided to go ahead with a deal with Iran after the leaders of Saudi Arabia, the United Arab Emirates, Qatar, Pakistan, Turkey, Egypt, Jordan and Bahrain urged him to do so. A huge US military presence will remain ready to strike at any time during the negotiations but Washington’s allies in the Gulf have made it clear that they have no more appetite for the fight.Please let me know what you think and send your comments, thoughts or suggestions for topics you would like to see covered to denis.globalbriefing@irishtimes.com