Executive Summary
From 2019 to 2025, VERTIC has been analysing the uranium enrichment programme of the DPRK. The following report lays out what has been established on the enrichment capacity of the DPRK, the technology enabling that capacity, and the implications for the DPRK’s stockpile of weapons-grade highly enriched uranium (HEU).
The DPRK has a sizeable enrichment programme, which continues to expand at the time of writing of this report. In September 2024 and January 2025, DPRK state media released images of Kim Jong Un touring the inside of the enrichment halls at Kangson and Yongbyon respectively. These photographs offered an amount of information about the DPRK’s enrichment capacity that was unprecedented in open sources, and much of our analysis in the past year has focused on integrating what was learned from these photographs into VERTIC’s previous HEU stockpile estimates issued in 2023.
The revised 2025 estimate for the DPRK’s HEU stockpile takes into account a higher density of centrifuges in the enrichment halls which were constructed more recently; it also narrows in on one set out of the scenarios which had been considered viable in 2023. Based on these adjustments, VERTIC assesses that the DPRK could have produced up to 1.8-2.6 tonnes of HEU by the end of 2025. VERTIC had previously assessed that the DPRK could have produced anywhere between 280 kilograms and 2.1 tonnes of HEU by the end of 2023.
The centrifuges shown in the photographs appear externally consistent with the dimensions of a G-2-type centrifuge, and with the description given by Dr Siegfried Hecker of the centrifuges he saw during his visit to Yongbyon in 2010. Although this does not preclude internal design improvements, VERTIC has assumed a separative work per centrifuge between 3.7 and 4.7 SWU for the purposes of this analysis. A simple sensitivity analysis for the impact of possible design improvements on the SWU has been carried out and is discussed in more detail in the body of the report.
Overall, it appears that the DPRK could have 10,000-13,000 centrifuges in working cascades, with the foundations for another possible enrichment hall at Yongbyon visible on imagery from this year. The visible cascades appear consistent with other known cascade designs for the production of low enriched uranium (LEU). However, this does not preclude the existence of unpictured cascades configured for HEU production or the recycling of enriched feed through LEU cascades.
