Trump Rebukes U.S. Proposal for 20-Year Moratorium on Iran’s Uranium Enrichment

“I’ve been saying they can’t have nuclear weapons … so I don’t like the 20 years,” President Donald Trump told the New York Post on April 14.

The president was responding to reports that U.S. negotiators had proposed a 20-year moratorium on Iran’s uranium enrichment — a key process for producing nuclear weapons fuel — during weekend talks in Islamabad. Iran reportedly countered with a five-year enrichment moratorium, which Washington rejected. The talks collapsed after 21 hours of negotiations.

Trump has long insisted that Iran agree to a permanent ban on enrichment. “I don’t want them [Iran] to feel like they have a win,” the president added regarding the 20-year proposal.

Trump’s instincts are correct. Even a two-decade suspension of enrichment would raise significant verification challenges and heighten the risk of Iranian cheating. By contrast, demanding the full, verified, and permanent dismantlement of Iran’s nuclear weapons program — including its enrichment capabilities — remains the only reliable way to ensure the regime cannot quickly restore a nuclear breakout capability.

Cheating and Verification Concerns Remain High

The full terms of the reported U.S. proposal remain unclear, particularly whether Iran would be required to fully dismantle its enrichment infrastructure during the 20-year period.

Yet under any deal, Iran should be required to eliminate centrifuge stockpiles, components, manufacturing and assembly capabilities, and any new enrichment sites — such as the Pickaxe Mountain facility that Trump has referenced in the past. Without these steps, Iran could simply stockpile equipment and wait out the remainder of Trump’s term in office before rapidly reconstituting its pathway to nuclear weapons fuel.

Tehran must also accept a permanent ban on plutonium reprocessing, the other route to nuclear weapons fuel, as well as on weaponization work or any activities aimed at building a nuclear device.

In 2020, Tehran began rapidly surpassing the limits of the 2015 nuclear deal, in part because the agreement allowed Iran to maintain stockpiles of advanced centrifuges, continue research and development on even more sophisticated designs, and sustain ongoing enrichment and uranium stockpiling. After the end of Trump’s first term and the Biden administration’s termination of the maximum pressure campaign, Iran was well positioned to begin stockpiling highly enriched uranium in 2021, setting the stage for a gradual breakout toward nuclear weapons.

Other key U.S. demands during the recent talks included Iran surrendering its existing stockpile of enriched uranium — including roughly 440 kilograms of highly enriched uranium — and fully dismantling the enrichment facilities struck by U.S. forces in June 2025 at Natanz, Isfahan, and Fordow. Washington may have also insisted on intrusive inspections, including full and restored access for the International Atomic Energy Agency (IAEA), and a formal renunciation of nuclear weapons development.

Full Nuclear Dismantlement Remains the Only Viable Path

With a new round of talks with Iran under consideration, Trump’s dissatisfaction with the proposed 20-year moratorium should prompt his negotiators to return to Washington’s core demand: a permanent ban on Iranian enrichment as well as plutonium reprocessing.

Only Iran’s full, verified, and permanent nuclear disarmament carried out while Trump is in office — including the complete elimination of its enrichment, reprocessing, and weaponization capabilities — can ensure the regime will not restore a nuclear weapons option.

Enforcing a permanent ban on Iranian enrichment would also allow the United States to credibly insist that Iran’s Arab neighbors refrain indefinitely from acquiring their own enrichment and plutonium reprocessing programs, reducing the risk of a regional nuclear arms race.

Andrea Stricker is a research fellow and deputy director of the Nonproliferation Program at the Foundation for Defense of Democracies (FDD). For more analysis from the author and FDD, please subscribe HERE. Follow Andrea on X @StrickerNonpro. Follow FDD on X @FDD. FDD is a Washington, DC-based, nonpartisan research institute focusing on national security and foreign policy.