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Russia-Ukraine War 2026
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Putin renews HEU offer at SPIEF

3 min read
19:51UTC

Vladimir Putin restated Russia's offer to take custody of Iran's 440.9 kg highly enriched uranium stockpile at the St Petersburg forum on 6 June. It is the same arrangement Trump barred on 27 May.

ConflictDeveloping
Key takeaway

Russia's HEU custody offer is the only live technical fix, and both Washington and Tehran have left it unanswered.

Vladimir Putin publicly restated Russia's standing offer to take custody of Iran's 440.9 kg stockpile of HEU (Highly Enriched Uranium, the 60 per cent material at the heart of the impasse) at the SPIEF (St Petersburg International Economic Forum) plenary on Saturday 6 June 1. He added that Russia is not arming Iran, that Iran has requested no weapons, and that both the United States and Israel privately told Moscow that recent shelling near the Bushehr nuclear plant was accidental.

The custodian arrangement hands Iran a way to satisfy the US demand to remove the stockpile without surrendering it to Washington. Trump rejected precisely that arrangement at a Cabinet meeting on Wednesday 27 May, when he barred both Russia and China from the role and told his negotiators not to rush.

The offer follows Araghchi confirming no progress on the nuclear file , and it sits unanswered. Mojtaba Khamenei's order to keep the HEU inside Iran still stands, and Tehran has sent no counter-proposal since hand-editing the disputed deal text . Russia gains from being the only mediator both Washington and Tehran will still take calls from, so the offer serves Moscow's interest while remaining a concrete, deliverable route out of the deadlock.

Deep Analysis

In plain English

Iran has built up 440.9 kilograms of uranium enriched to 60 per cent purity. At 90 per cent, uranium becomes weapons-grade. The US and Israel want this stockpile removed from Iran or destroyed. Russia has repeatedly offered to take it to Russian territory for safekeeping. Putin made this offer again at SPIEF (St Petersburg International Economic Forum), Russia's annual economic conference, on 6 June. Iran's Supreme Leader has ordered the uranium stays inside Iran. As of 6 June, no custody transfer has been agreed and the war continues. Putin also said Russia is not supplying Iran with weapons, a denial that matters because US military assessments have previously linked Chinese and Russian equipment to Iran's continued military capability.

Deep Analysis
Root Causes

Russia's repeated reaffirmation of the HEU custodian offer across SPIEF (6 June), a Moscow press conference (10 May, ) and Peskov's statement (13 April, ) reflects a consistent Kremlin strategic interest: to prevent a US-Iran settlement that excludes Moscow from the regional architecture. Putin told SPIEF that 'initially everyone agreed' the uranium would go to Russia, a claim he has sole-sourced; if true, it positions the US as the party that hardened terms, not Iran.

Rosatom evacuated approximately 180 of its 200-plus staff from Bushehr by 16 April , leaving roughly 20 managers on site. Russia lacks the operational capacity to implement the custody arrangement even if Iran agreed.

Escalation

Putin's public denial that Russia is arming Iran is the most operationally significant element of the SPIEF statement. If accurate, it reduces the risk of a direct US-Russia confrontation over arms flows. The separate claim that both the US and Israel privately told Moscow the Bushehr shelling was accidental is unverifiable from the Russian side alone, but if true, it indicates an active US-Russia back-channel on escalation thresholds that has not been publicly acknowledged.

What could happen next?
  • Consequence

    Russia positions itself as indispensable to any Iran settlement, complicating a purely US-Iran bilateral agreement.

    Medium term · Assessed
  • Risk

    Khamenei's order that the HEU stays inside Iran makes the custodian offer operationally moot until the Supreme Leader's position changes or his capacity to enforce it erodes.

    Short term · Assessed
  • Opportunity

    If Iran's economic collapse deepens, the custodian offer becomes Tehran's least-humiliating exit from the HEU impasse, enabling a deal without surrendering directly to the US.

    Medium term · Reported
First Reported In

Update #119 · Trump's Iran deal: 95% done, 0% signed

Press TV· 6 Jun 2026
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