North Korea nuclear capacity expands, IAEA chief says

North Korea has sharply expanded activity linked to nuclear weapons production , according to Rafael Grossi, Director-General of the International Atomic Energy Agency (IAEA), who spoke in Seoul on Wednesday, April 15, 2026.

Grossi said operations at the Yongbyon nuclear site have grown quickly, pointing to increased work across multiple parts of the complex. He cited the reactor, the reprocessing unit, and the light-water reactor as areas where activity has expanded, and he also referred to the activation of other facilities.

The IAEA’s periodic assessments, Grossi said, indicate a major improvement in the Democratic People’s Republic of Korea’s ability to produce nuclear weapons. He described the estimated output as sufficient to support a few dozen warheads, reflecting what he called a significant increase in overall capacity.

Grossi also highlighted construction of a new facility that he said resembles the Yongbyon enrichment plant. He said this suggests a substantial rise in the DPRK’s enrichment capacity, even as the agency has not had on-site inspections in the country since 2009.

North Korea carried out its first nuclear test in 2006 and remains subject to United Nations sanctions tied to prohibited weapons programs. Officials in Pyongyang have repeatedly said the country will not give up its nuclear arsenal, a position that continues to shape regional security calculations and diplomatic constraints.

On the question of external support, Grossi said the IAEA has not observed direct Russian assistance in North Korea’s nuclear development. At the same time, he noted that Pyongyang has provided military support to Russia’s invasion of Ukraine and has reportedly received military technology in return.

For markets and policymakers, the IAEA’s description of expanded enrichment and reprocessing-related activity adds to uncertainty around sanctions enforcement, regional risk pricing, and the security environment in Northeast Asia. However, the agency’s lack of access since 2009 remains a key limitation, leaving important details about the scale and pace of developments dependent on periodic assessments rather than on-site verification.