Iran's Assembly of Experts Warns Negotiators: Nuclear Program Is Off the Table

On June 27, 2026, Iran's Assembly of Experts—the powerful clerical body that supervises the Supreme Leader—issued a rare public warning to the country's nuclear negotiators. The message was blunt: negotiators must strictly observe Supreme Leader Mojtaba Khamenei's declared red lines in the ongoing talks with the United States, and they must not repeat what the Assembly called "the mistakes of previous negotiations" .

The Assembly's statement framed the Supreme Leader's directives as a "religious obligation" and declared that violating them "is not permissible under any circumstances." It specifically insisted that Iran's nuclear program must remain entirely outside the scope of negotiations, meaning no foreign oversight or limitation on enrichment activities should be accepted as a subject of bargaining . The warning reflects deep anxiety among hardliners that negotiators may concede too much in the push for a final deal.

The June 15 Islamabad Memorandum of Understanding

This warning came less than two weeks after the U.S. and Iran signed a 14-point Memorandum of Understanding (MOU) on June 15, 2026—known as the Islamabad Memorandum—that established a framework for ending hostilities .

Ceasefire and Military Provisions

• Immediate and permanent cessation of military operations on all fronts, including Lebanon .
• The U.S. agreed to immediately lift its naval blockade of Iranian ports .
• Both sides committed to refraining from the use or threat of force .

60-Day Timeline

• The MOU establishes a 60-day diplomatic phase (running from June 15) during which the parties must negotiate a comprehensive final deal covering nuclear issues, sanctions relief, and regional security .
• During this period, the ceasefire remains in effect .

Sanctions Relief and Economic Terms

• Iran may begin exporting oil immediately upon signing the MOU .
• The U.S. agreed to waive sanctions on Iranian oil exports and related services for the 60-day period .
• Iranian frozen assets—estimated at between $80-100 billion—are to be released as part of the framework .
• Iran agreed to provide safe passage for commercial vessels through the Strait of Hormuz with no charge for 60 days .

Nuclear Provisions

• Nuclear talks were deferred entirely to the 60-day negotiation phase—the MOU itself does not resolve the enrichment question .
• Iran committed to refrain from developing nuclear weapons, but the specifics of enrichment limits and stockpile disposition were left open .

The Core Sticking Point: Iran's Enriched Uranium Stockpile

The most contentious unresolved issue is the fate of Iran's stockpile of near-weapons-grade uranium . According to the IAEA, Iran holds approximately 441 kilograms of uranium enriched to 60%—one technical step away from the 90% needed for a nuclear weapon . IAEA Director General Rafael Grossi has estimated that this stockpile is enough to produce material for more than 10 nuclear warheads if further enriched .

The U.S. demands that this stockpile be shipped out of Iran, diluted, or otherwise disposed of . But in late May 2026, Supreme Leader Mojtaba Khamenei issued a firm directive: "Not one gram leaves." The order, confirmed by two senior Iranian sources to Reuters, mandates that all enriched uranium remain inside Iranian territory . The directive flatly contradicts the core U.S. demand and is widely reported as the single greatest obstacle to a comprehensive deal .

Iran's nuclear chief, Mohammad Eslami, has also stated that any final deal must include recognition of Iran's right to enrich uranium—another red line that clashes with Washington's position .

Parallel Debates and Opposition

In Washington:

• Senate Republicans demanded a formal vote on the MOU, criticizing the White House for keeping Congress in the dark and for Vice President JD Vance signing the document without prior congressional consultation .
• Conservative lawmakers and analysts suggested Congress could derail or reject the MOU, citing intense internal turmoil within the Republican Party over whether the deal gives away too much before resolving the nuclear question .
• The Congressional Progressive Caucus had already opposed supplemental funding for the Iran war, and the MOU's deferral of nuclear issues drew criticism from both hawks (who say it concedes too much) and doves (who say it does not go far enough) .
• Senate Democrats made nine attempts to advance a war powers resolution to formally end hostilities, with the latest failing in a 47-48 vote .

Among Iran's Hardliners:

• The Assembly of Experts' warning itself reflects hardliner anxiety that negotiators may overstep the Supreme Leader's red lines .
• Hardliners view the MOU as a potential trap that secures sanctions relief and Hormuz reopening without guarantee of preserving Iran's enrichment program—the very issue Khamenei has declared non-negotiable .
• Some hardliners have publicly argued that the 60-day timeline is a U.S. tactic to extract nuclear concessions after Iran has already delivered on Hormuz and oil sanctions, leaving Tehran with less leverage .

Israel has also signaled deep concern. The U.S. understanding is that Israel may view the failure to resolve the uranium stockpile as an unacceptable security risk, and the MOU does not address Israeli security guarantees .

What Happens Next?

The MOU paused the shooting and reopened the Strait of Hormuz, but the 60-day clock is now ticking on the single hardest issue: whether Iran will ever agree to remove its near-weapons-grade uranium from the country, given Khamenei's firm "not one gram leaves" directive . Both Washington and Tehran face intense domestic opposition that could collapse the framework before the 60 days expire. The Assembly of Experts' warning makes clear that the clerical establishment in Iran will fight any deal that touches what it sees as non-negotiable nuclear rights.