Analysis of IAEA Iran Verification and Monitoring and NPT Safeguards Reports — September 2025

Excerpt

This report summarizes and assesses information in the International Atomic Energy Agency’s (IAEA) quarterly report, dated September 3, 2025: Verification and monitoring in the Islamic Republic of Iran in light of United Nations Security Council resolution 2231 (2015), including Iran’s compliance with the Joint Comprehensive Plan of Action (JCPOA), as well as new findings in the IAEA’s companion report, NPT Safeguards Agreement with the Islamic Republic of Iran.  Context and commentary are added on aspects omitted from these reports.

Highlights

• The military attacks destroyed or made inoperative all of Iran’s installed centrifuges—almost 22,000 gas centrifuges—at Iran’s three enrichment sites.  They destroyed Iran’s ability to make gas centrifuges, severely degraded its capabilities to research and develop them, and destroyed Iran’s ability to make uranium hexafluoride.  In essence, the attacks destroyed Iran’s gas centrifuge enrichment program.
• With the massive destruction of its gas centrifuge program and installed centrifuge cascades, for the first time in over 15 years, Iran has no identifiable route to produce weapon-grade uranium (WGU) in its centrifuge plants.  In addition, the attacks caused immense destruction to Iran’s ability to make the nuclear weapon itself.  For the first time in over 15 years, no breakout estimate to WGU is included in the Institute reporting on the IAEA reports, since to do so would require unsubstantiated speculation about the existence and operability of centrifuges that were not destroyed in the war, such as centrifuges already made but not yet deployed, as well as about the availability of enriched uranium stocks, whether near five percent, near 20 percent, or 60 percent enriched uranium.
• Iran’s stock of 60 percent enriched uranium can be used directly in a nuclear explosive.  Practically, 40 kg are sufficient for an implosion-type nuclear weapon and double that amount, or 80 kg, is sufficient for a gun-type nuclear explosive device.[4]  Iran’s ability to develop and make nuclear explosives has been severely degraded by the war.  Thus, estimates of the time it would take Iran to turn the HEU into a nuclear explosive are fraught with uncertainty.
• The IAEA reports that Iran intended to establish a new enrichment plant, named the “Isfahan Fuel Enrichment Plant” (IFEP) at the Nuclear Reactors Fuel Company (NRFC) site, although the IAEA reports do not provide its location.  The authors assess that it is in the mountain complex at the main Esfahan nuclear site.  The IAEA language implies that portions of the facility had already been built, although centrifuges were unlikely to have been installed.  U.S. attacks destroyed the three tunnel entrances to this site, which included ventilation equipment servicing the tunnel complex.  Iran subsequently gained access to at least one of three tunnel entrances, but visible damage remains, and the plant does not appear to be ready for operations.
• Iran held enriched uranium at all three main nuclear sites: Natanz, Fordow, and Esfahan.  There are no indications that Iran moved stocks outside of these three sites, but the exact location and amounts of enriched uranium within facilities at the sites is unknown.
• Iran likely stored most of its lower enriched uranium stocks at Natanz.  Fordow and Natanz also made HEU and held stocks of HEU there, with Fordow holding the far larger amount.  However, it is well known that Iran had moved significant portions of its 20 and 60 percent stockpiles to the Esfahan site, and portions of these stocks, along with lower enriched uranium stocks, were in buildings subsequently destroyed or damaged. Fearing an attack, Iran likely moved portions of its enriched uranium stocks, particularly its HEU stock at Esfahan, into the Esfahan tunnel complex associated with the nuclear site.  When it was building the tunnel complex two decades ago, Iran declared it as a potential storage site for nuclear material in the event of military strikes and the IAEA has confirmed that the tunnel complex is used for the storage of enriched material.
• The IAEA reports that it “lost continuity of knowledge in relation to the current inventories of nuclear material in Iran, including low enriched uranium (LEU) and high enriched uranium (HEU), which urgently needs to be addressed.”  It adds that it had “already lost continuity of knowledge in relation to the production and current inventory of centrifuges, rotors and bellows, heavy water and UOC [uranium ore concentrate], which it will not be able to restore.”
• The IAEA reports no new progress and no engagements with Iran regarding unresolved safeguards issues that the agency has been investigating since 2018.

Andrea Stricker is deputy director of the Nonproliferation and Biodefense Program at the Foundation for Defense of Democracies (FDD) and an FDD research fellow.