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Iran Conflict 2026
12JUN

Trump vetoes Iran's only uranium exit

4 min read
09:18UTC

Asked at a 27 May Cabinet meeting whether Iran could ship its uranium to Russia or China, Donald Trump said "No, I wouldn't be comfortable", shutting the one storage route that could have bridged the deal.

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ConflictDeveloping
Key takeaway

On Day 90 the only actor visibly slowing an Iran settlement is the US President, by act not word.

Donald Trump rejected both Russia and China as custodians for Iran's highly enriched uranium at a 27 May Cabinet meeting in Washington, telling reporters "No, I wouldn't be comfortable" with either 1. The answer killed the only third-country storage option anyone had floated. Iran holds roughly 440.9 kg of uranium enriched to 60%, far above reactor fuel and a short technical step from weapons-grade, at the Isfahan tunnel complex. The International Atomic Energy Agency (IAEA), the UN body that verifies nuclear material, has had no access since 28 February, so no outside party can even confirm where the stockpile now sits.

Supreme Leader Mojtaba Khamenei had ordered the material to stay inside Iran on 21 May , reversing a pre-war offer to export half and removing the export option outright. Sending it abroad under a neutral host was the workaround, and Vladimir Putin had pitched Xi Jinping in Beijing on 21 May that Russia would hold it. By barring both Russia and China without naming a fourth host, Trump struck out the last route between the US demand that the uranium leave and Iran's refusal to let it go, hardening the three-way split that had already produced contradictory accounts of the deal's nuclear terms .

The same afternoon, Trump told his negotiators "not to rush into a deal" and said Iran's hope of outlasting him "won't work because I don't care about the midterms" 2. Marco Rubio, his Secretary of State, had said 24 hours earlier the deal could be finalised that day. A fairer reading deserves its sentence: with Iran refusing both to surrender the uranium and to readmit inspectors, barring Moscow and Beijing as custodians is defensible non-proliferation rather than gamesmanship.

The ledger cuts against that reading. The White House presidential-actions index shows zero Iran instruments signed across 90 days of war 3: no ceasefire order, no use-of-force authorisation, nothing directing or limiting the naval blockade. The veto is an act, not a post, and it points the same way 90 days of silence have: away from closure.

Deep Analysis

In plain English

Iran has a stockpile of uranium enriched to 60% purity. Normal power-station fuel sits around 5%. Weapons-grade uranium needs to be about 90% pure. Iran's 60% material is not yet weapons-grade, but it is close enough that further enrichment to weapons-grade would be a relatively short technical step. The US wants Iran to get rid of this stockpile before a deal is agreed. The idea was to ship it to a third country, like Russia, for safekeeping. Trump has now said he doesn't trust Russia or China to hold it securely. So there is no agreed destination, and Iran itself has said the material is staying inside the country. Both sides have now closed off the workaround diplomats had been quietly working towards for weeks: Trump vetoed the custodian, and Khamenei barred the export. Neither move has been reversed.

Deep Analysis
Root Causes

The third-country custody impasse has two structural roots that pre-date 27 May.

First, the IAEA was locked out of Iran at the start of the conflict following the Majlis's 221-0 vote suspending all cooperation. Without IAEA inspectors, no independent party can verify where the 440.9 kg stockpile actually is, whether it has been further enriched since the lock-out, or whether a transfer has been completed honestly.

Russia and China both lack the independent inspection capacity to substitute for the IAEA. Trump's stated discomfort with both as custodians is partly a verification problem: neither country would accept intrusive IAEA-style access on its own soil to monitor the transferred material.

Second, Mojtaba Khamenei's 21 May directive ordering the stockpile to remain in Iran removed Iran's negotiating flexibility on the very item the US identified as the last sticking point. Rubio named HEU turnover as the final unresolved issue; Khamenei's directive closed the export option, and Trump's 27 May veto closed the custodian workaround, in the same week.

Escalation

The 27 May veto raises the diplomatic ceiling required to reach any agreement. Any path forward now requires either a new custodian state that Trump trusts, a mechanism for Iran to dispose of the material inside Iran itself with verified destruction, or an Iranian reversal of Khamenei's 21 May directive. None of those three options is currently on the table.

What could happen next?
  • Consequence

    With Russia and China vetoed, there is no third-country custody mechanism available. Any resumed negotiation must find a new sequencing bridge for the HEU question or defer it entirely to Phase 2.

    Immediate · Assessed
  • Risk

    Iran's 440.9 kg stockpile at 60% enrichment continues to accumulate without IAEA oversight. The breakout timeline shortens every week the IAEA remains locked out, regardless of diplomatic progress on other tracks.

    Short term · Assessed
  • Precedent

    Trump's explicit rejection of Russia and China as custodians formalises a great-power split over the Iran nuclear file. Any eventual settlement must now be US-managed or US-endorsed, eliminating multilateral burden-sharing.

    Medium term · Reported
  • Risk

    If negotiations collapse permanently, Iran's enrichment programme resumes unrestricted. The Arms Control Association estimates Iran could reach weapons-grade enrichment within weeks from the current 60% baseline.

    Long term · Suggested
Sources:CNBC·PBS News·PBS News
Mentions:Donald Trump →Iran →Russia →China →Vladimir Putin →Xi Jinping →Marco Rubio →Pakistan →Strategic Council on Foreign Relations →Isfahan →Tasnim →Tennessee →Arms Control Association →Tehran →Beijing →Gaddafi →Libya →Kazakhstan →NATO →Moscow →Washington →United States →Council on Foreign Relations →Isfahan tunnel complex →IAEA →Mojtaba Khamenei →White House →
First Reported In

Update #110 · Trump vetoes Iran's only uranium exit

CNBC· 28 May 2026
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Causes and effects
Caused by
Khamenei orders the uranium to stay
Khamenei's 21 May directive ordering the HEU stockpile to stay in Iran created the impasse that Trump's veto of Russia and China as custodians closes off; the directive removed the export option and the veto removes the workaround.
Occurred 21 May 2026
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Hegseth threatens Iran strikes in Singapore
Hegseth's Shangri-La remarks linking Hormuz to Taiwan follow Trump's barring of China as HEU custodian on 27 May; China's scholars-only delegation is consistent with that exclusion.
Occurred 30 May 2026
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Trump signs nothing on Iran in two days
The 4 June airlift disclosure advances the 27 May custodian-veto beat; both concern the disposition of the same 440.9 kg HEU stockpile.
Occurred 4 Jun 2026
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This Event
Trump vetoes Iran's only uranium exit
The veto removes the only third-country custody arrangement that could have reconciled the US demand to surrender Iran's uranium with Tehran's refusal to give it up.
Led to
Iran airs draft deal; US calls it fake
Trump's Cabinet veto of third-country custody options sharpened the document war by making the MOU's bracketed Hormuz-sovereignty and US-force-posture clauses the only remaining open-text disputes.
Occurred 27 May 2026
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US sanctions the strait it will reopen
Trump's decision not to sign the MOU on 28 May followed his 27 May Cabinet instruction to slow down and bar Russia and China as HEU custodians.
Occurred 28 May 2026
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Iran and US publish two different deals
Trump barring Russia and China as HEU custodians on 27 May left the deal's hardest item without an agreed location, amplifying the incompatibility of the two published MOU texts.
Occurred 29 May 2026
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Different Perspectives
Oil markets and Lloyd's of London
Oil markets and Lloyd's of London
Brent fell to $89.25 on ceasefire probability, not new barrels, with traders voting for Trump's deed over Tehran's denial. Lloyd's has not repriced Hormuz war-risk cover because its trigger requires a UN Security Council resolution or government certification, so tanker insurance costs remain elevated regardless of the spot move.
Pakistan and Qatar mediators
Pakistan and Qatar mediators
Pakistan's Mohsin Naqvi was in Tehran for his second visit in under a week, using the Pakistan-Qatar channel that delivered April's ceasefire after an identical public-denial cycle. The channel carries both civilian and military buy-in from Islamabad, the only configuration Iran's split command cannot dismiss as a partial signal.
India
India
India summoned the US Deputy Chief of Mission after three Indian sailors were killed aboard MT Settebello, the first formal grievance from a major non-belligerent directed at US enforcement. Indian seafarers supply roughly 12 per cent of the global maritime workforce; their presence on third-flag Gulf tankers is structurally inevitable regardless of bilateral diplomacy.
Islamic Revolutionary Guard Corps (IRGC)
Islamic Revolutionary Guard Corps (IRGC)
The IRGC declared Hormuz closed on 11 June while civilian negotiators were on the same mediation channel, then issued no public comment on the MoU framework. Its silence on the framework, rather than any foreign ministry statement, is the operative approval signal; the corps' unilateral Hormuz closure shows it did not treat the diplomatic track as binding on its operations.
Iran foreign ministry (Baghaei)
Iran foreign ministry (Baghaei)
Esmail Baghaei told IRNA that reports of a finalised deal were 'merely speculation' and that Iran had 'not yet made a final decision'. The denial is structurally identical to Iranian foreign ministry statements during the April ceasefire talks, which produced a binding text within 48 hours of the same language.
Trump administration / CENTCOM
Trump administration / CENTCOM
Trump cancelled the third strike day and called the MoU 'very strong' and almost ready to sign, while CENTCOM kept tanker enforcement running in the same 24-hour window. The administration is simultaneously withdrawing the military pressure it claims drove the deal and sustaining the enforcement campaign it is trying to trade away.