North Korea has accumulated enough weapons-grade nuclear material to more than double its current atomic weapons stockpile, a new report from a UK-based think tank has revealed. According to an analysis conducted by the Royal United Services Institute (RUSI), Kim Jong-un’s regime may now possess sufficient fissile material—uranium and plutonium—to significantly increase the number of nuclear warheads it can produce.
The report estimates that North Korea already holds between 80 and 90 nuclear warheads. With the new stockpile of enriched materials, Pyongyang could potentially add hundreds of additional warheads to its growing nuclear arsenal. This development marks a concerning escalation in North Korea’s nuclear capabilities, heightening tensions with neighboring South Korea and Japan, as well as the United States.
The key ingredient in a nuclear weapon is fissile material, which initiates a powerful chain reaction when manipulated under specific conditions. This reaction leads to the devastating explosions associated with atomic bombs. North Korea has steadily ramped up its ability to produce two types of fissile material—plutonium and highly enriched uranium—both critical to the production of nuclear weapons.
RUSI’s report, based on a combination of satellite imagery, North Korean state media reports, and assessments from public appearances by Kim Jong-un at nuclear enrichment facilities, suggests that Pyongyang now has enough fissile material to develop between 80 and 200 additional short and medium-range warheads. These weapons, often referred to as “disco balls” by analysts due to their spherical design, could have a yield of around 10 kilotons, similar to the bomb that destroyed Hiroshima in 1945.
Furthermore, RUSI estimates that Kim Jong-un could manufacture between 25 and 35 strategic thermonuclear warheads. These more advanced, second-generation weapons can reach intercontinental targets, including U.S. cities, and are deliverable via ballistic missiles. This could mark a shift in North Korea’s ability to threaten both regional adversaries and far-flung foes like the United States with equal precision.
The combination of these short, medium, and long-range nuclear weapons allows North Korea to achieve its two primary objectives with its nuclear program: deterring conventional military threats from neighboring countries like South Korea and Japan, and posing a credible nuclear threat to the U.S. mainland. The RUSI report suggests that Pyongyang’s current fissile material stockpile could allow the country to construct more weapons than it immediately needs for defensive purposes, further underscoring North Korea’s long-term ambitions to cement its status as a nuclear power.
“Given its fissile-material inventory at the end of 2023, North Korea might have already developed approximately 21–23 composite (plutonium and highly enriched uranium) thermonuclear warheads,” said RUSI in its report. However, North Korea’s ability to further expand its arsenal is limited by its access to plutonium, which is more difficult to produce and acquire in significant quantities than uranium.
While North Korea has claimed that its nuclear weapons program is necessary for its survival and to counter perceived threats from the U.S. and its allies, experts believe Pyongyang is unlikely to stop expanding its arsenal. As its nuclear program evolves, it will likely continue accumulating more weapons-grade material than it needs for immediate defense purposes.
North Korean state media has increasingly showcased the country’s nuclear facilities and weapons capabilities in recent years. Kim Jong-un himself has been featured in numerous public appearances at nuclear enrichment sites, where he often inspects the technology and machinery involved in weapons production. These highly choreographed visits are not only a signal to the international community of North Korea’s growing nuclear prowess but also serve as a point of national pride for a regime that views nuclear weapons as a symbol of power and prestige.
The RUSI report draws attention to how Kim’s media appearances and North Korea’s overall propaganda campaign have consistently emphasized the development of a versatile arsenal. The aim, analysts believe, is not only to bolster the country’s nuclear deterrence but also to ensure that the regime has the capacity to “win” any military conflict that might erupt on the Korean Peninsula.
To that end, North Korea has been working to diversify its nuclear capabilities by developing smaller-yield, tactical nuclear weapons that can be used in regional conflicts, as well as more powerful strategic weapons capable of reaching targets far beyond its borders. This dual-capability arsenal could be a significant game-changer in how North Korea approaches its nuclear strategy and how the international community responds to it.
North Korea’s aggressive pursuit of a more formidable nuclear arsenal has already stoked fears among its neighbors and adversaries. South Korea and Japan, both within striking distance of Pyongyang’s short and medium-range missiles, view the situation with growing alarm. In response to North Korea’s nuclear ambitions, the U.S. has increased its military presence in the region and bolstered its alliances with Seoul and Tokyo.
However, as the RUSI report indicates, North Korea is not solely focused on its regional adversaries. Its strategic thermonuclear weapons are designed to defeat U.S. missile defenses and pose a credible threat to the U.S. mainland. This capability, should it be fully realized, would fundamentally shift the security dynamics in East Asia and beyond.
Sarah Laderman, a senior analyst for the Open Nuclear Network, which was contracted by RUSI to carry out part of the research, notes that Pyongyang’s strategy reflects a nuanced approach to building a multi-faceted nuclear arsenal. “They’re really focusing on a dual-capable arsenal. They’re looking to deter the U.S., which is further away, so they need a more strategic arsenal. But they also need to deal with regional adversaries like South Korea and Japan,” Laderman said.
North Korea’s pursuit of both short-range tactical weapons and long-range strategic missiles demonstrates its broader aim to structure its nuclear capabilities in a manner similar to other established nuclear-armed states. By doing so, Pyongyang ensures it has a flexible deterrent capable of meeting threats from both near and far.
Speculation is mounting that North Korea could conduct a new nuclear weapons test soon, particularly in light of the upcoming U.S. presidential election. Experts believe that a test could be intended to increase pressure on Washington and potentially force a shift in U.S. policy toward North Korea.
However, some analysts, including South Korea’s spy agency, argue that North Korea may delay any nuclear tests until after the election. They suggest that Pyongyang may prioritize completing a series of tests related to its long-range ballistic missile program before conducting another nuclear detonation. These tests could further refine its ability to deliver nuclear warheads to distant targets, a crucial component of its strategic deterrent against the U.S.
North Korea’s refusal to engage in denuclearization talks has left the international community scrambling for solutions. Despite years of U.S.-led sanctions and diplomatic efforts, Pyongyang has only accelerated its nuclear and missile programs. Kim Jong-un’s regime has declared that its status as a nuclear-armed state is “irreversible,” and it has even enshrined this position in its constitution.
The inclusion of nuclear weapons in North Korea’s constitution represents a stark break from the past, when denuclearization was at least theoretically on the table in negotiations. This move signals that Pyongyang has no intention of abandoning its nuclear ambitions anytime soon.
Sarah Laderman emphasizes that any meaningful dialogue with North Korea will likely require a shift in the West’s approach. “So long as countries insist on only talking about denuclearization, we don’t see North Korea coming to the table,” she said. North Korea has made it clear that it views its nuclear weapons as essential to its survival, and it wants the West to recognize its right to possess them.