Vladimir Putin has proposed that both Iran and the United States transfer enriched uranium to Russian custody, a move designed to break the diplomatic deadlock over Tehran’s nuclear program.

The Trump administration has flatly rejected the idea, insisting that US custody over Iran’s nuclear material is the only acceptable arrangement.

What Russia is actually proposing

Putin first floated the uranium storage arrangement in June 2025 and has reiterated it multiple times since, including during discussions in March 2026. Kremlin spokesman Dmitry Peskov confirmed as recently as April 2026 that Russia still considers its proposal very much on the table.

Russia managed Iran’s low-enriched uranium under the 2015 Joint Comprehensive Plan of Action, the landmark nuclear deal that saw Tehran agree to limit its nuclear activities in exchange for sanctions relief. Putin has pointed to that precedent as proof that Russia has both the infrastructure and the track record to handle this kind of operation.

Iran has approximately 450 kg of uranium enriched to 60% purity, a concentration level that, with further processing, could potentially yield material for over 10 nuclear weapons. The 2015 deal involved low-enriched uranium — a substantially less dangerous category of material.

Why Washington says no

The Trump administration’s position is unambiguous. US custody over Iran’s nuclear stockpile is the floor, not the ceiling, of any potential agreement. Iran has shown no willingness to hand its enriched uranium directly to the United States. The US refuses to let Russia serve as intermediary. And Russia keeps offering a solution that neither party across the table will accept.