Assessing the damage to the nuclear programme

Key centrifuge facilities: destroyed

Damage: The US and Israeli strikes damaged many sites dedicated to centrifuge production (manufacturing and assembly) and have likely destroyed many of Iran’s roughly 18,000 operating centrifuges at Natanz and Fordow.

Why it matters: The destruction of centrifuges and related facilities sets back weaponisation, if Iran has to produce more machines or set up a new enrichment facility.

Residual dangers: Right before the June strikes, Iran had nearly 4,000 centrifuge units that were not operating. That made them less vulnerable to blast effects, and they may prove salvageable to use for weaponisation. A third enrichment facility at Isfahan adds further uncertainty: its status and potential centrifuges installed there are unknown. Undeclared centrifuges elsewhere are also a possibility.

Uranium yellowcake facility: likely destroyed

Damage: The strikes destroyed Ardakan, Iran’s only facility for milling uranium and producing yellowcake—concentrated uranium that is the precursor material to producing uranium gas and, ultimately, enriched uranium.

Why it matters: Potentially delays weaponisation if Iran restarts its nuclear programme from scratch and needs to process uranium ore.

Residual dangers: Iran may have existing stockpiles of yellowcake that were not destroyed. It could also rebuild the facility.

Uranium conversion facility: destroyed

Damage: Iran’s only uranium conversion facility (also known as the UF6 production plant) at Isfahan has been destroyed.

Why it matters: Potentially delays weaponisation.

Residual dangers: If Iran cannot access its stockpile of highly enriched uranium—or chooses not to access it to evade detection—then it would likely build a new covert uranium conversion facility to produce the gas necessary for enrichment.

Highly enriched uranium stockpile: largely intact but trapped

Damage: The IAEA believes much of Iran’s 440.9kg stockpile of 60% highly enriched uranium has been buried deep in the bombed Isfahan facility since June 2025.

Why it matters:The stockpile is a key building block for weaponisation. It is estimated to be enough for nine to ten nuclear bombs if enriched to weapons-grade.

Residual dangers: Though largely trapped, Iran could still retrieve the stockpile. US intelligence agencies, however, maintain surveillance of the Isfahan site and  say they have high confidence they could detect and respond to any retrieval attempt. It would be very difficult for Western actors themselves to safely remove this stockpile without Iranian cooperation. Iranian authorities may have also moved some highly enriched uranium stockpile to other unknown sites prior or during the June bombing.

Uranium metal conversion: primary hub destroyed

Damage: The strikes destroyed Iran’s main facility at Isfahan.

Why it matters: It could delay weaponisation.

Residual dangers: Iran can build a new uranium metal conversion facility reasonably swiftly or use existing lab facilities at other locations to produce uranium metal.

Nuclear knowledge: disrupted

Damage: Israel assassinated an estimated 11-20 Iranian nuclear scientists.

Why it matters: The assassinations disrupt atomic research and hobble the recruitment and training of new scientists to revive the nuclear programme and advance weaponisation.

Residual dangers: Iran is likely to have trained many scientists, meaning it is impossible to bomb its knowledge out of existence.

Explosives testing capability: disrupted

Damage: Israeli strikes on Taleghan 2 facility are likely to have penetrated a containment vessel that Iran appeared to be in the process of burying, potentially to protect it from such attacks.

Why it matters: The vessel could have been used for testing explosives relevant for building a nuclear weapon.

Residual dangers: Iran has previous experience with high explosives testing and could build a new containment vessel.