Tehran Likely to Reject U.S. Nuclear Proposal Amid Damning IAEA Report
The Islamic Republic is expected to reject the recently delivered written U.S. nuclear proposal, reportedly dismissing it as a “non-starter” due to what Tehran views as “radical demands,” particularly the U.S. insistence on zero uranium enrichment on Iranian soil and insufficient clarity on potential sanctions relief. This diplomatic development coincided with the release of a damning report by the International Atomic Energy Agency (IAEA). The agency reported that the Islamic Republic produced approximately 136 kg of uranium enriched to 60% since February, marking a nearly 50% increase over the past three months, and underscored Tehran’s continued refusal to answer critical questions about undeclared sites that at different points were involved in the Islamic Republic’s nuclear weapons program.
This escalating situation underscores the urgency for the United States and its allies to maintain zero enrichment as a non-negotiable policy stance, establish credible contingency plans, and maximize international pressure through snapback sanctions and strategic communications.
The Bottom Line
The IAEA’s recent report confirms the Islamic Republic has accumulated over 400kg of uranium enriched to 60%—enough for ten nuclear weapons if further enriched to 90%, which is only a short step away. This marks a substantial increase in the regime’s 60% uranium stockpile amid ongoing negotiations with the United States.
The IAEA emphasized that Tehran has not provided satisfactory answers to questions regarding several undeclared nuclear sites in the country.
The E3 (UK, France, Germany) may now use the IAEA report as a basis for triggering snapback sanctions at the UN, a move the regime fears and has warned will carry “consequences.”
The United States, via Oman, delivered a new nuclear deal proposal to Tehran on May 31. Reports suggest it included provisions for uranium removal, centrifuge destruction, and a regional enrichment consortium.The Islamic Republic is expected to reject the offer in line with their strategy of drawing out negotiations, and is reportedly “drafting a negative response to the U.S. proposal.”
The enrichment dispute remains the central sticking point in negotiations. Both Tehran and Washington describe their position as a red line. The regime rejects the U.S. demand for zero enrichment as “domination,” reaffirming its so-called right to enrich uranium under the Treaty on the Non-Proliferation of Nuclear Weapons (NPT) and resorts to rhetoric about a nonexistent “fatwa,” or religious edict from the Supreme Leader, falsely claiming it prohibits nuclear weapons.
Details of the IAEA Report
On May 31, the IAEA circulated a report to its Board of Governors revealing that the regime’s current enrichment rate is roughly equivalent to producing enough material for one nuclear weapon per month. The agency said this development poses a “serious concern.”
The IAEA emphasized its inability to verify the peaceful nature of Iran’s nuclear program, citing Tehran’s failure to answer questions regarding three undeclared nuclear sites—Lavisan-Shian, Varamin, and Turquzabad.
IAEA investigations were a factor in nuclear negotiations between the U.S. and Tehran during the Biden administration as well. Since 2018, the agency has been investigating evidence that the regime did not properly disclose certain nuclear materials and related activities as mandated by its safeguards obligations.
In 2022, IAEA Director Rafael Grossi warned that, until Iran cooperates with the investigation, the “Agency cannot confirm the correctness and completeness of Iran’s declarations under its Comprehensive Safeguards Agreement,” leading the IAEA Board of Governors to pass a resolution urging Iran to “fulfill its legal obligations” and “clarify and resolve all outstanding safeguards issues.” Like we see today, the regime deployed its standard playbook of accusing the IAEA of politicization, refusing to cooperate.
Grossi has warned that without access to sites and answers to unresolved questions, “any agreement on Iran is just a piece of paper.”
The Islamic Republic’s refusal to provide access to senior inspectors and its continued obstruction of verification efforts represent a clear violation of the IAEA Safeguards Agreement and NPT obligations.
The report also says that there is a certain amount, roughly 10 kg, of fissile material that has not been accounted for by the IAEA. This could potentially lead to diverted fissile material which could be used or transferred by the regime even after the signing of a deal.
Tehran’s Response to the Report
The regime, looking to draw out negotiations and avoid snapback sanctions, dismissed the IAEA report as politically motivated. In a joint statement, the Islamic Republic Foreign Ministry and the Atomic Energy Organisation of Iran (AEOI) accused the agency of acting under Western pressure and violating its non-partisan mandate.
The statement claimed the IAEA “went beyond its domain of duties” and that its findings were “repetitive” and lacked credibility.
Foreign Minister Abbas Araghchi and other senior officials warned that Tehran would “act to protect its rights and legitimate interests” if the IAEA or E3 pursue “politicized actions,” referencing the potential initiation of snapback measures.
Foreign Ministry Spokesperson Esmail Baqai dismissed the IAEA’s recent findings, accusing the agency of aligning with Israeli efforts to "continue its Iranophobia project" and influence U.S. foreign policy.
Head of the AEOI, Mohammad Eslami, called the report a “political move” meant to block Tehran from benefiting from the expiration of JCPOA restrictions and accused Grossi of “pursuing ambitions” to become UN Secretary General by pleasing the West.
The regime denied any deviation from peaceful purposes, citing Khamenei’s fatwa and the presence of IAEA inspectors, while continuing to claim that enrichment is its inalienable right under international law.
The U.S. Proposal and Stalemate Over Enrichment
U.S. officials, through Omani mediation, presented Iran with a new nuclear proposal on May 31, reportedly including a call for a regional enrichment consortium located outside Iran involving the U.S., Saudi Arabia, and others.
During a live broadcast interview, Eslami dismissed the consortium proposal as an outdated initiative which has never benefited Iran, but also noted that the decision does not fall in his hands.
Tehran is expected to reject the proposal, reportedly dismissing it as a “non-starter.”
Foreign Ministry Spokesperson Esmail Baqai on June 2 further minimized the significance of the U.S. proposal, signaling Tehran’s intent to dismiss any proposals containing "radical demands," while anonymous sources in regime media labeled the proposal "illusory," "unilateral," and an unsuitable foundation for negotiation.
The Trump administration continues to insist on zero enrichment as a condition for any deal, with President Trump reiterating his belief that the regime may soon cave on May 30: “They don’t want to be blown up… I think that[a deal]could happen in the not-too-distant future.”
According to an official close to the regime’s negotiating team, “the U.S. stance on enrichment on Iranian soil remains unchanged” in the recent proposal, “and there is no clear explanation regarding the lifting of sanctions."
Tehran has rejected these demands outright. On May 31, Araghchi said, “Whether or not we need enrichment—and we do—it’s unacceptable for some to impose restrictions on us just because they consider themselves powerful.”
International Reactions
Israeli Prime Minister Benjamin Netanyahu’s office responded to the IAEA report by stating it “serves as a clear warning sign” that the regime in Iran is determined to acquire nuclear weapons.
President Trump has urged Netanyahu to delay any potential Israeli military action pending the outcome of negotiations, but has also emphasized that the military option remains on the table.
The E3 may now use the IAEA report to initiate the snapback of UN sanctions under UNSCR 2231, which would reimpose all international restrictions lifted under the 2015 JCPOA.
Tehran has warned that triggering snapback would “end Europe’s role” in negotiations and could prompt the regime to withdraw from the NPT altogether.
Western diplomats are increasingly alarmed by recent comments from Khamenei advisers suggesting the Supreme Leader may reconsider his so-called “ban” on nuclear weapons if pressure mounts.
Policy Recommendations
Stick to the two month deadline that President Trump outlined at the start of negotiations. Though the start of the two months was not specified, assuming the clock started on the first round of talks, the deadline should be June 12. If no deal is reached by June 12, the United States should withdraw from negotiations and shift its policy on Iran towards a combination of a third-way approach of Maximum Pressure on the regime and Maximum Support for the Iranian people.
Hold the Islamic Republic accountable at the IAEA Board of Governors by formally declaring Iran in violation of its NPT obligations and referring the case to the UN Security Council.
Support the E3 in triggering snapback sanctions prior to the October 18 sunset clause, ensuring no permanent erosion of international restrictions on the regime in Iran’s nuclear activities.
Prepare contingency measures—including coordinated U.S.-Israeli military planning.
Publicly expose the regime’s duplicity and violations through strategic communications and amplify the voices of Iranian dissidents and experts warning of the nuclear threat.