The world’s most consequential nuclear standoff is being conducted largely in the dark. The International Atomic Energy Agency, the institution mandated to prevent nuclear proliferation, has admitted it cannot determine whether Iran’s new underground enrichment site at Isfahan is an operational facility or an empty hall. This is the defining condition of the most volatile diplomatic moment the Middle East has seen in decades.

When Israel launched its first strikes against Iranian nuclear infrastructure last June, Iran held 440.9 kilograms of uranium enriched to 60 percent purity, a stockpile sufficient, by IAEA estimates, to produce as many as 10 nuclear weapons should Tehran choose to weaponize it. The IAEA also tracked a convoy removing what was believed to be a substantial portion of it from the Fordow facility shortly before hostilities began. Where it went remains unverified.

The agency has been reduced to monitoring vehicular movements around tunnel complexes using commercially available satellite imagery. This is the surveillance architecture of a nonproliferation regime under siege.

Iran’s nuclear opacity and its ambiguity predate the conflict by decades. Fordow’s existence was only disclosed to the IAEA in September 2009, after Western intelligence services had already exposed it. Iran had been constructing the site since 2006 without any declaration to the watchdog. Isfahan is following the same playbook, with construction taking place first and disclosure consistently delayed, allowing the uncertainty itself to serve a strategic purpose.

France, Germany and the UK this month jointly told the IAEA Board of Governors that the agency had been unable to account for Iran’s uranium stockpile, including highly enriched uranium equivalent to more than 10 IAEA “significant quantities,” the threshold used to calculate weapons potential.

Iran, for its part, wrote last month that “in light of prevailing circumstances, the expectation of the normal implementation of safeguards in Iran is, from legal, technical, and operational perspectives, untenable.” Tehran is formally asserting that opacity is not a violation but a legitimate posture, a precedent with profound consequences for every other state watching how far the nonproliferation regime can be bent before it breaks. Iran remains the only state without nuclear weapons to have produced 60 percent highly enriched uranium at scale. 

At the heart of this landscape lies a paradox. The less verifiable Iran’s nuclear program is, the greater Tehran’s negotiating leverage becomes. Far from being an obstacle, uncertainty is the very core of Iran’s strategy.

A clear example of this was seen in February’s Geneva talks. After three rounds of indirect negotiations, Omani Foreign Minister Badr bin Hamad Al-Busaidi announced that Iran had agreed to never stockpile enriched uranium, suspend enrichment for three years and accept long-term restrictions capping purity at 1.5 percent, all subject to international verification. These are concessions of extraordinary scope, which would have seemed unthinkable during the 2013-2015 Joint Comprehensive Plan of Action talks, when Iran rejected even modest enrichment caps despite being in a comparatively weaker position.

But there is a critical flaw in that Iran offered to relinquish something of which the current quantity cannot be independently verified. The IAEA is unable to confirm the precise amount of enriched uranium in Iran’s stockpile, making any future verification of compliance equally uncertain. This offer, while broad in scope, is inherently unfalsifiable and that is precisely what makes it advantageous for Tehran. It projects a message of moderation to Washington and Brussels while preserving operational ambiguity on the ground.

Regional actors, including Saudi Arabia, the UAE and Qatar, are also affected. They are not focused on Iran crossing a nuclear threshold but on the risks of forcing a definitive outcome. A clear binary, where Iran either openly declares a weapon or is militarily prevented from doing so, would force every regional power to take sides, with irreversible consequences. Ambiguity, however, allows space for hedging.

This dynamic also affects the mediators. Oman and Qatar, once brokers facilitating backchannel diplomacy, have been compromised by the conflict, bearing the direct consequences of Iranian retaliation and strikes from the US and Israel. Turkiye, Egypt and Pakistan have stepped in. However, their goal is no longer resolution but disaster prevention. The diplomatic horizon has shifted from solving the nuclear issue to stopping the situation from worsening each week. 

What is eroding in plain sight is the international nonproliferation architecture, with Iran expertly exploiting every vulnerability. After the June 2025 war, Tehran suspended all cooperation with the IAEA, only to agree in Cairo in September to resume inspections, before halting implementation once again following the reimposition of UN sanctions. This cycle of partial engagement, provocation and withdrawal is carefully calibrated to keep the regime technically compliant and ensure it remains beyond meaningful constraint.

Iran’s formal claim that normal safeguards are untenable under current conditions poses a significant danger, as other states are closely watching. If a nation can cite military pressure as grounds for withdrawing from verification obligations without facing effective consequences, it undermines the entire treaty system. The IAEA was never designed to rely on satellite imagery alone.

Nuclear ambiguity is, in the short term, stabilizing. No party is likely to initiate a war over an uncertain stockpile. In the medium term, however, it is corrosive, preventing the region from building reliable security structures, poisoning diplomacy by making verification impossible, and gradually normalizing the idea that a state can remain on the nuclear threshold indefinitely without any formal accountability.

Across the region, governments are recalibrating to the persistent possibility of an Iranian nuclear weapon. Saudi Arabia has accelerated its civilian nuclear program, Turkiye openly discusses its right to enrichment and smaller Gulf states are forging new security deals with Washington. Every neighbor has been forced into a perpetual state of defense, draining diplomatic energy and military resources against a threat that remains unconfirmed yet ever-present.

For Israel, it creates a constant state of existential alert that impacts every political decision. For the US, it ties down more strategic focus on the region. And for Iran’s potential allies, the uncertainty surrounding Isfahan makes alignment too costly and distance too risky. The result is not just a more dangerous Middle East but a fundamentally altered nuclear order. Iran has proven that a state does not need to cross the nuclear threshold to reshape the strategic landscape around it.

• Zaid M. Belbagi is a political commentator and an adviser to private clients between London and the Gulf Cooperation Council.

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