Despite ongoing nuclear talks with the United States, Iran has sharply increased its stockpile of near weapons-grade uranium, prompting the International Atomic Energy Agency (IAEA) to issue its most damning report yet. The agency accused Tehran of concealing nuclear material and running a secret weapons-related program until the early 2000s.

The IAEA reported that Iran’s stockpile of 60% enriched uranium grew from 274.8 kg to 408.6 kg since February—an increase of 50%. This quantity is enough to produce approximately 10 nuclear weapons, a significant escalation considering Iran is the only non-nuclear weapons state enriching uranium to such high levels.

U.S. officials warn that it would take Iran less than two weeks to convert this material to 90% weapons-grade. Though Tehran insists its nuclear program remains peaceful, the IAEA said it “cannot verify” this claim.

Secret Nuclear Sites and Undeclared Material

The IAEA's comprehensive report, released May 31, detailed Iran's failure to cooperate with a years-long probe into undeclared nuclear material. Investigators identified Lavisan-Shian, Varamin, and Turquzabad as sites of unreported nuclear activities. At Lavisan-Shian, uranium metal was used for neutron source production—a component tied to nuclear detonation tests.

The agency concluded Iran maintained a “structured nuclear program” involving undeclared material until at least 2018 and stored radioactive assets at Turquzabad until that year.

Growing Pressure for UN Action

European countries and the U.S. are preparing to submit a resolution declaring Iran in violation of its obligations under the Non-Proliferation Treaty. A senior diplomat confirmed that the issue will be raised at the IAEA Board of Governors meeting beginning June 9. A formal finding of non-compliance would mark the first in nearly two decades and could trigger the snapback of U.N. sanctions, which are set to expire in October.

Israel welcomed the report, with Prime Minister Benjamin Netanyahu declaring, “The world must act now… Iran is totally determined to complete its nuclear weapons program.”

Iran’s Warning and Global Stakes

Iran has threatened to exit the NPT and alter its nuclear doctrine if sanctions are reinstated. While structured weapons development is believed to have ceased in 2003, the IAEA and U.S. intelligence agencies say weapons-related experiments have continued.

Director General Rafael Grossi called the enrichment trend “of serious concern,” emphasizing that no other non-nuclear weapon state produces uranium at such levels.

Background on the 2015 Nuclear Deal and Its Collapse

The 2015 Joint Comprehensive Plan of Action (JCPOA) placed strict but temporary limits on Iran’s nuclear activities in exchange for sanctions relief. Former President Trump withdrew from the deal in 2018, claiming it was insufficient. Since then, Tehran has accelerated its enrichment program and restricted IAEA inspections.

Five rounds of indirect U.S.-Iran talks have so far failed to produce a new framework agreement. Analysts warn that further escalation could collapse diplomacy altogether and open the door to military confrontations in the region.