It took the United States and Iran most of February through June to reach a memorandum of understanding. It took less than 48 hours for that agreement to hit its first real test.
The deal, signed by President Trump and Iranian President Masoud Pezeshkian, was supposed to move into its next phase this week with technical negotiators meeting in Switzerland to start hammering out the details — enrichment limits, sanctions relief, the future of Iran’s nuclear sites. Instead, the meeting didn’t happen. Vice President JD Vance, who was set to lead the U.S. side, stayed home. Iranian negotiators didn’t show either.
That the two sides can’t agree on why is, in some ways, the more telling story.
Two Explanations, One Stalled Process
Washington’s version is mundane: scheduling. A White House spokesperson said the delegation was ready to leave at a moment’s notice but that final arrangements simply hadn’t come together — adding, almost wearily, that these things rarely go smoothly. Switzerland’s government echoed that framing, saying it stood ready to host and that preparations were continuing.
The account coming out of the region is sharper. Several officials briefed on the talks say Iran balked specifically over Lebanon — where Israeli strikes intensified in the days right after the memorandum was signed — and over comments from Israeli Prime Minister Benjamin Netanyahu that Tehran read as a violation of the deal’s spirit before the ink was even dry. By that account, Tehran wanted assurance the fighting would actually stop before sitting down to negotiate what comes next. Pakistan, which has helped broker contacts between the two sides, was reportedly caught off guard by Iran’s decision not to travel.
Both things can be true at once — a scheduling mess on top of a substantive dispute — and that ambiguity is itself a symptom of how fragile the arrangement still is.
The Part of the Deal Nobody Signed
The hardest piece of this puzzle isn’t really about the U.S. and Iran at all. It’s about Israel and Hezbollah, neither of which put their name on the agreement, even though the agreement is supposed to end their fight. Iran has made clear it’s prepared to let that front stay hot if it has to, given how much weight Hezbollah carries as its most important ally in the region. Israel, meanwhile, has its own complaints — chiefly that the deal buys Tehran time to regroup rather than actually disarming it.
Vance tried to talk Israel down from that position publicly on Thursday, telling reporters that Israel needed to respect a process he described as good for the region as a whole. Netanyahu’s public posture suggests he isn’t there yet; he’s continued to signal Israel will act unilaterally if it judges Iran to be edging toward a weapon, deal or no deal.
What’s Actually Left to Decide
Strip away the diplomatic drama and the to-do list is long. Negotiators still have to settle how much uranium Iran can enrich, what becomes of its nuclear infrastructure, whether and how sanctions come off, and how — or whether — Iran’s missile arsenal and its network of regional allies get addressed at all. None of that has been touched yet. The Switzerland session was meant to be where that work began, and it’s now sitting on a 60-day clock that started ticking the moment the memorandum was signed, postponement or not.
Vance, Increasingly the Face of This
Whatever happens next, Vance has clearly become the administration’s point person on Iran, working alongside Secretary of State Marco Rubio, Jared Kushner, and envoy Steve Witkoff. Trump has been careful to describe it as a group effort rather than handing Vance sole ownership, but it’s Vance’s travel plans making headlines, not anyone else’s.
On the Iranian side, the cast of characters has changed too. Mojtaba Khamenei has stepped into his father’s role as Iran’s leader after an airstrike killed the elder Khamenei last month, and Iranian officials are said to be wary of certain American negotiators they blame for past talks collapsing right before military action followed.
Where This Leaves Things
No new date for the Switzerland meeting has been announced. Both governments are describing this as a delay rather than a breakdown — but a 60-day window that opens with a missed first meeting and live fighting in Lebanon isn’t exactly off to a reassuring start. Whether this becomes a footnote or the moment the deal started unraveling probably depends on what happens in Lebanon over the next few days, not on anything either delegation says about scheduling.