Secret Nuclear Expansion Uncovered at Key North Korean Site
Fresh satellite imagery has exposed North Korea's construction of a covert uranium enrichment plant at its primary nuclear research centre, directly supporting leader Kim Jong Un's ambitious plan to dramatically expand the country's nuclear arsenal this year.
The images, captured throughout October and November 2025 and meticulously examined by Washington-based monitoring group 38 North, reveal ongoing modernisation and expansion efforts across the sprawling Yongbyon Nuclear Scientific Research Centre. This facility represents North Korea's most crucial site for producing both plutonium and enriched uranium - the two essential components for manufacturing nuclear weapons.
New Facility Mirrors Suspected Covert Plant
Analysis of the high-resolution pictures indicates Pyongyang is likely constructing a substantial, heavily secured compound northeast of the site's radiochemical laboratory. The structure features a two-storey design with a central hall measuring approximately 120 metres by 47 metres, closely resembling the layout and dimensions of Kangson - another suspected covert enrichment facility long believed to support the North's nuclear weapons programme.
According to the detailed report from 38 North, construction at this new facility has become "most active since the start of 2025", with six possible heat exchangers recently appearing on the building's southeast side. These units typically serve to cool centrifuges and maintain the stable temperatures essential for uranium enrichment processes.
Analysts suggest the installation of these exchangers indicates that interior work is progressing rapidly, even as support buildings and connecting corridors continue to take shape around the main compound. Additional work to build up land surrounding a support building south of the suspected enrichment site is also underway, though the exact purpose of this structure remains unclear.
Aligning With Kim's Nuclear Directive
This heightened activity coincides with broader modernisation efforts at Yongbyon - the heart of North Korea's nuclear production infrastructure. The complex serves as the country's only known producer of plutonium and a significant source of enriched uranium.
The developments directly follow Kim Jong Un's instruction earlier this year to accelerate nuclear material production. During visits to weapons-related institutes in January, he described 2025 as a "crucial year" for "bolstering up the nuclear forces" and demanded officials "overfulfill" plans for weapons-grade output.
"These improvements all serve to help fulfil Kim's call for exponential growth of its nuclear weapons arsenals," the 38 North report concluded.
Satellite imagery also reveals rapid expansion of radioactive-waste storage near Yongbyon's Old Waste Site. A new semi-buried concrete facility with nine roof hatches appears covered with earth, while fresh excavation nearby suggests another containment vault is under development.
Regional Security Implications
North Korea's progress in uranium enrichment represents a major concern for regional rivals and neighbours. Highly enriched uranium proves easier than plutonium to engineer into weapons, and while plutonium facilities are large and produce detectable radiation, uranium centrifuges can operate almost anywhere - including small factories, caves, underground tunnels, or other difficult-to-access locations.
The images additionally confirm the continued operation of the key plutonium-producing 5MWe reactor throughout late 2024 and 2025, despite roof repairs and exterior refurbishment earlier this year.
This new analysis emerges as South Korea warns against escalating risks of accidental clashes with the North. South Korean president Lee Jae Myun recently stated, "We are in a very dangerous situation where accidental clashes could break out at any time," while emphasising that Seoul has "no intention of pursuing unification by absorption" and remains committed to the Nuclear Non-Proliferation Treaty.
