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Iran Conflict 2026
9MAR

IAEA: 441kg enriched uranium untracked

2 min read
05:12UTC

The UN nuclear watchdog disclosed that 440 kg of weapons-grade-threshold uranium has been unverified for eight months, with movement detected near stockpile sites.

ConflictDeveloping
Key takeaway

The enriched uranium is unaccounted for; the "degraded programme" narrative is incomplete.

IAEA Director General Rafael Grossi told CBS Face the Nation on 22 March that Iran possessed 440.9 kg of uranium enriched to 60% U-235 according to pre-strike inspection records. At 60% enrichment, that is enough fissile material for approximately seven nuclear weapons if further enriched to weapons-grade 90%. 1

Inspectors have had no access to previously declared inventories for more than eight months. Iran suspended cooperation with the IAEA and restricted inspectors from bombed sites. The agency detected "movement near stockpile sites" but cannot verify what has moved or where. Most of the stockpile is believed buried in tunnels at Isfahan.

Grossi put it plainly: "You cannot unlearn what you've learned." Iran retains the scientific and industrial base to rebuild. Netanyahu had claimed Iran can no longer enrich uranium , but the IAEA disclosed that same week that Iran has a new underground enrichment facility at Isfahan, its fourth, with inspectors denied access. The centrifuge infrastructure may be degraded. The enriched material itself is a separate question, and it remains unanswered.

Deep Analysis

In plain English

Before the war began, UN weapons inspectors had confirmed Iran held 440 kilograms of uranium enriched to 60% purity. To make a nuclear weapon you need uranium enriched to about 90%. At 60%, Iran's stockpile is not yet weapons-ready, but it is close: further enrichment would take weeks on available centrifuges. The problem is that inspectors have not been allowed to verify where this stockpile is for over eight months. The bombs and airstrikes have been aimed at enrichment machines and production facilities. The actual uranium material is something different. The IAEA, the UN body that tracks this, detected movement near storage sites but cannot say what moved or where it went. The public narrative is that US and Israeli strikes have set back Iran's nuclear programme. That may be true for the factories and machines. The 440 kilograms of already-processed uranium is a separate, unanswered question.

Deep Analysis
Root Causes

Iran's exclusion of IAEA inspectors began before the war, under the Joint Comprehensive Plan of Action breakdown from 2019 onward. By the time strikes began in February 2026, inspection access was already limited to declared sites. The war provided cover for restricting it further, but the verification gap predates the conflict.

The physical concealment is a separate driver. Iran's deep-tunnelling programme at Isfahan, Fordow, and Natanz was explicitly designed to move enriched material beyond the reach of bunker-busting munitions. The fourth underground facility disclosed by the IAEA in March 2026 suggests the dispersal architecture was built years in advance of the conflict.

What could happen next?
  • Risk

    If the 440 kg stockpile has been dispersed to undeclared sites, no future ceasefire agreement can verifiably denuclearise Iran without renewed IAEA access that Iran's five conditions make unlikely.

  • Consequence

    The 'degraded programme' narrative underpins domestic US public support for the war; the stockpile uncertainty undermines the achievement claim.

First Reported In

Update #50 · Houthis join; Iran holds two chokepoints

IAEA / CBS News· 28 Mar 2026
Read original
Different Perspectives
Oil markets / Lloyd's underwriters
Oil markets / Lloyd's underwriters
Futures markets priced CENTCOM's strikes-complete statement as a de-escalation signal and pushed Brent down 1.7 per cent to $94.71, even as the IRGC declared Hormuz closed. Lloyd's war-risk premiums held elevated because institutional de-listing requires a UN Security Council resolution that Russia and China have just shown they will block.
Pakistan (mediator)
Pakistan (mediator)
Interior minister Mohsin Naqvi carried dual civilian and military letters to Mojtaba Khamenei in Tehran on 6-7 June with no public response. The IRGC's Hormuz closure on 11 June shows the corps is acting independently of the channel Pakistan is using, making the mediation structurally unable to produce a binding commitment without direct IRGC access.
Russia and China
Russia and China
Russia and China voted against GOV/2026/40 at the IAEA Board, following through on the blocking position coordinated with Grossi in Geneva on 5 June; both states continue to oppose Western institutional pressure on Iran at every multilateral venue.
E3 and IAEA (UK, France, Germany)
E3 and IAEA (UK, France, Germany)
The E3 co-sponsored IAEA resolution GOV/2026/40, adopted 21-3-10 on 10 June, demanding Iran disclose 440.9 kg of unaccounted HEU and admit inspectors to four denied facilities. The 10 abstentions and Russia-China noes leave any Security Council referral without a viable enforcement path.
IRGC / Iran military command
IRGC / Iran military command
The corps declared Hormuz closed to all traffic on 11 June and claimed two vessels struck, overriding the MoU its own civilian negotiators were pursuing through Pakistan. The closure order used the Persian Gulf Strait Authority apparatus to convert a toll mechanism into a military prohibition.
Trump administration / CENTCOM
Trump administration / CENTCOM
CENTCOM completed a second day of strikes on Tehran, Sirik and Minab, rejected the IRGC Hormuz closure as inconsistent with observed transit, and said strikes were complete. Hegseth framed the bombing explicitly as the negotiation: the method is coercive deal-making with no stated pause threshold.