North Korea is no longer just a pariah state with a few crude bombs buried in mountain tunnels. 

Under Kim Jong-un, it is turning into a full-blown nuclear factory, churning out the fuel for dozens of new warheads and testing missiles that can turn almost anywhere in the world into radioactive wasteland.  

In the hills at Yongbyon, the heart of the regime’s nuclear machine, satellite images now show a landscape of new buildings, fresh concrete, steaming reactors and growing fields of radioactive waste.

To experts who have tracked the site for years, it looks like a nuclear production line being pushed to its limits. At the centre of it all stands the nation’s dictator, Kim, who told his scientists that 2025 was a ‘crucial year’ for ‘bolstering up the nuclear forces’. 

His message to them has been simple and clearly effective – more bombs and more often. Just last month, he unveiled what his regime described as ‘the most powerful nuclear strategic weapon’, the Hwasong 20, which can reach any part of the US. 

For years, world leaders warned that if diplomacy failed, North Korea would become a serious nuclear power. That moment has now arrived. What makes North Korea so frightening is not only the nuclear weapons it has built, but the leadership in charge of them. 

Kim is unpredictable and rules through fear. He has also never shown the caution of other nuclear states and has tested more missiles than his father and grandfather combined. 

He has threatened neighbouring countries, defied sanctions, and watched the world fail to stop him. 

With every year that passes, he grows more confident that nobody will dare take his arsenal away. Experts have warned that his confidence is dangerous because it gives him room to build without restraint. 

Dr Edward Howell, an expert on North Korean relations at Oxford University, told Daily Mail that labelling Kim and his country as ‘irrational’ is a ‘dangerous misunderstanding’. 

He said: ‘Kim Jong-un is neither irrational nor crazy. Rather, he has a clear strategy in mind, namely, to behave delinquently and reap rewards in so doing, from the international community, without giving away his ‘treasured sword’ of nuclear weapons.’

Now, 38 North, a website that tracks North Korea, has revealed that new satellite images show that the country is working around the clock to meet Kim’s demands for more nuclear weapons. 

Commercial satellite imagery has revealed the extent of work at Yongbyon. This image from October this year shows the possible uranium enrichment facility at Yongbyon

Kim Jong-un in a picture released by his government in October 2025. The North Korean dictator has instructed his scientists to ramp up their nuclear weapons production 

Inside the Yongbyon complex, 60 miles north of Pyongyang, which has been the core of North Korea’s nuclear programme since the late Cold War, fresh activity is visible everywhere. 

Dr Howell explained: ‘The recent developments at Yongbyon make clear what we have known for a while: the Kim regime’s ultimate goal is for North Korea to be recognised as a de facto nuclear-armed state. 

‘As Kim Jong-un said only recently, North Korea will never give up its nuclear programme. Pyongyang has long pursued highly enriched uranium, even in the 1990s, while it froze its plutonium programme at Yongbyon.’

The old 5 megawatt reactor at the facility that once produced plutonium for the first nuclear tests continues to run. Satellite images show constant heat signatures from its cooling system and a series of upgrades around its exterior.

Roof panels have been replaced, walls have been repainted, and construction equipment has been spotted in nearby yards. 

The reactor may be old, but it is being cared for and has become a reliable source of plutonium production. 

A short walk away, though nobody can see it except from space, is an experimental light water reactor that has been in development for more than a decade. 

It has gone through irregular cycles of cooling-water discharge, which analysts say reflects pre-operational testing, meaning it is close to becoming operational. 

Once active, it would produce a different kind of nuclear material and could support more advanced warhead designs in the future. 

Its presence alone transforms Yongbyon from a limited facility into a multi-reactor complex capable of long-term production and expansion. 

Even heavy flooding that damaged the old river dam could not slow it down for long.

Engineers built a temporary embankment, then began work on a stronger dam to secure stable water levels, a clear indication that North Korea is not letting nature get in the way of nuclear progress.

Fresh satellite imagery reveals cranes and construction material surrounding the ageing 5MWe reactor, confirming continuous maintenance to keep plutonium production running 

Although heavy rainfall damaged the old dam, engineers built a temporary work and hastily built a stronger dam, ensuring that production was not slowed down

The Experimental Light Water Reactor, in development for more than a decade, continues observable cooling water discharge

The most dramatic development in the complex is the rapid rise of a suspected new enrichment area to the north east of the radiochemical laboratory. 

Earlier images showed open ground, but newer ones show a huge building with a central hall, surrounded by a secure boundary. 

The entire structure was roofed within months. By early autumn, the outer walls looked complete and fresh concrete connected the main hall to its side buildings.

A covered walkway links one block with another for weatherproof transfers of sensitive materials or personnel. Rows of heat exchangers line the outside wall, which hints at what lies within. 

Centrifuges that enrich uranium generate heat and require steady temperature control. The layout and equipment match what analysts expect to see at a modern enrichment plant. 

Kim’s call for ‘exponential’ growth in nuclear material appears to be turning into real infrastructure.

The appearance of fresh waste storage vaults adds more proof. One bunker sits partly buried, with roof hatches arranged in an organised pattern. 

In October, the sides of the structure were packed with earth, leaving only the top exposed. Another excavation sits next to it, showing North Korea is preparing more underground storage. 

There is a suspected underground radioactive waste storage at the facility, underscoring Kim’s plans for long-term production 

Waste is an unavoidable part of plutonium and uranium processing. Larger waste areas usually mean increased production. 

Long-term waste expansion signals that North Korea is planning not a short burst of activity but a permanent rise in nuclear output.

Away from the reactors and enrichment sites, the entire Yongbyon complex shows signs of renewal. 

Buildings once linked to agricultural use have been cleared, and in their place are new support facilities are rising. 

Older industrial structures near the uranium conversion area now have large holes in their roofs, likely part of a full refurbishment or possible replacement. 

The message across the site is hard to miss – North Korea has decided that Yongbyon will remain its most important nuclear asset for the coming decades. It is not winding down. It is being reinforced.

This rapid physical expansion comes at a moment when North Korea’s overall warhead numbers are rising. 

Independent estimates suggested that by the start of this year, the country had about 50 assembled warheads with enough fissile material for around 90 more if all available resources were weaponised. 

The hydrogen fluoride handling building shows multiple roof openings, a sign that major refurbishment or internal equipment replacement is underway in this critical conversion area

Other studies suggest Pyongyang may hold up to two tonnes of highly enriched uranium, which could support dozens of additional weapons depending on design.

Some forecasts by defence analysts in the region say the total stockpile could rise to more than 150 warheads within a few years if current rates continue. 

Long-range projections by think tanks in Seoul and Washington suggest that North Korea could reach hundreds of warheads by the 2030s, putting it within range of the smaller Cold War nuclear powers.

These figures are alarming not just because of the numbers but because of the kind of weapons North Korea is believed to be developing. Early designs were single-stage fission devices with limited yield. 

Now the country appears to be moving into more complex territory. The likely output of Yongbyon’s reactors and enrichment halls opens the possibility of boosted fission weapons, which use small amounts of tritium to create far more powerful blasts.

There are also concerns about miniaturised warheads that can fit on a variety of missiles. 

At the same time as its factories grow, North Korea’s nuclear weapons are becoming more advanced than many people realise. Most of the warheads publicly discussed by analysts are based on fission designs, which use plutonium or highly enriched uranium to create powerful blasts.

The International Atomic Energy Agency says that the 5 megawatt reactor at Yongbyon has long produced the plutonium needed for these weapons. 

The country’s early nuclear devices produced relatively small yields. The first test in 2006 was under one kiloton according to seismic readings studied by the Comprehensive Nuclear Test Ban Treaty Organisation. Later tests were far larger. 

A 2017 detonation measured around 140 to 250 kilotons depending on analysis. Several independent monitoring groups believe this shows that North Korea can now build weapons many times stronger than the bomb dropped on Hiroshima.

North Korea is believed to have miniaturised some of its warheads. This assessment has been repeated by the South Korean Ministry of Defence and by the US Defence Intelligence Agency. 

Miniaturised designs matter because they can fit on a wide range of missiles. North Korea has already shown the ability to combine its warheads with short-range and medium-range systems. 

South Korean and Japanese military tracking confirms that many of these missiles can reach their targets in minutes, leaving very little time for warning or interception.

The country’s long-range missiles are even more worrying. The Hwasong 20, unveiled in October, has been described as the next generation of intercontinental ballistic missiles, with a range of 9,300 miles and the ability to reach and flatten any part of the US.

Kim’s other nuclear weapons, the Hwasong 14 and Hwasong 15 intercontinental missiles, have demonstrated flight paths consistent with the ability to reach cities thousands of miles away. 

During a military parade on October 10, North Korea unveiled the Hwasong 20, which it described as ‘the most powerful nuclear strategic weapon’

Analysts say the Hwasong 17, unveiled in 2020, is even larger and could carry multiple warheads and decoys, although this has not been confirmed by flight tests. It has been speculated that it could evade some of the best missile defences in the world. 

The Hwasong 18 also has a range of 9,300 miles and uses solid fuel, confirmed by both the US and South Korean militaries. Solid fuel missiles can be launched with little preparation time and are harder to detect before firing.

The damage these weapons could cause depends on their yield and where they are aimed. A basic fission weapon of ten kilotons can flatten buildings within a large radius. 

A device in the range of the 2017 test would destroy many miles and produce deadly radiation. Researchers note that even a single detonation in a populated area would overwhelm emergency services and create long-term contamination. Multiple detonations would be impossible to manage.

Dr Howell believes this is a worrying threat that should not be taken lightly. He also notes that Vladimir Putin’s involvement should not go unnoticed. 

He explained: ‘North Korea’s nuclear threat to the East Asian region and the world must be taken seriously, as it is only going to increase in severity. Of note, we must remember that ongoing cooperation between Russia and North Korea looks unlikely to abate even in the event of an end to the Ukraine War. 

‘Russia looks to continue supplying missile and military technology to North Korea, which raises the concerning prospect that North Korea’s ability to expand the scope and sophistication of its nuclear programmes will only accelerate.’

Experts also warn that North Korea’s nuclear strategy increases the danger. In 2022, the regime passed laws that allow the use of tactical nuclear weapons at the start of a conflict if it believes an attack is coming. 

South Korea’s National Intelligence Service described this as a major shift that lowers the threshold for nuclear use. Tactical nuclear weapons are smaller than strategic ones but would still kill large numbers of people and contaminate wide areas.

Taken together, these assessments show that North Korea now has nuclear weapons that can be delivered by a variety of missiles, launched quickly, and used in different types of conflict. 

Dr Howell agrees with other experts who have warned that Kim would not hesitate to use nuclear weapons if his back is against the ropes.

He said: ‘Whilst Kim Jong-un knows that any use of nuclear weapons in the event of any war on the Korean Peninsula will lead to the end of his regime, he has not ruled out the offensive usage of nuclear weapons in any such event.’

Each improvement in missile reliability makes its growing warhead stockpile even more dangerous.

The expansion also matters because it signals the failure of previous diplomatic efforts. When Kim met Donald Trump in 2018, there was real hope that the nuclear programme could be paused or even reversed. 

The following year, Kim offered to dismantle Yongbyon in exchange for partial relief from sanctions. 

Trump refused and insisted that North Korea hand over its entire nuclear, chemical and biological arsenals in a single deal. That meeting collapsed with no agreement.

Since then, North Korea has gone back to what it does best – building, testing, and refusing to answer calls from the outside world. Whatever chance existed for a negotiated freeze seems to have now passed. 

According to Dr Howell, North Korea is not even ‘pretending’ to show that it is interested in any discussion. He said: ‘Any form of diplomacy takes two to tango, and since the inconclusive summit between Donald Trump and Kim at Hanoi in 2019, North Korea has not even been pretending to negotiate with the US and South Korea. 

‘Now that Pyongyang has Russia as its newfound treaty ally, from which it has been getting humanitarian assistance, material support, financial assistance, as well as sanctions evasion, the Kim regime may plausibly choose to delay any talks with the US or South Korea. 

‘At the same time, if Kim Jong-un can secure a meeting with Trump wherein Trump tacitly acknowledges North Korea’s nuclear status, then it would be a victory for the North Korean leader.’

The growth of Yongbyon shows that North Korea no longer seeks small concessions. It wants a long-term guarantee of survival, and the leadership believes nuclear weapons are the only way to achieve that. 

Kim Jong-un walking in front of a Hwasong-17 intercontinental ballistic missile. Analysts say it can carry multiple warheads

Kim has watched global events and concluded that countries without nuclear arms can be invaded or toppled. Countries with nuclear weapons cannot. Analysts say this belief drives everything North Korea is doing today. 

It is preparing for a future in which conflict with the outside world is always possible, building weapons that make any strike against it unthinkable, and shaping itself into a state that relies entirely on nuclear deterrence.

The consequences of this shift are bleak – a larger arsenal makes each crisis more dangerous. A single miscalculation, accidental launch or misunderstood military exercise could escalate into a nuclear exchange. 

North Korea’s missile men have tested rockets with erratic flight paths and experimented with new fuels. Any of these steps could produce a catastrophic accident. 

A failed missile could fall on a neighbouring country and trigger retaliation. A misunderstanding during a tense moment could lead to an order that cannot be withdrawn. 

There is also the ever-present danger of proliferation. North Korea has a long history of trading military technology for money or political support. It once helped Syria build a suspected nuclear reactor. 

It has supplied missiles and artillery to countries that could not get them elsewhere. With a larger nuclear programme comes a larger network of engineers, labs and transport routes. 

The more material that flows through Yongbyon, the more chances there are for small amounts of it to disappear. Even a few grams of stolen plutonium or enriched uranium would be enough to spark a global search and a cascade of fear.

The expansion of Yongbyon also places new pressure on South Korea, Japan and the wider region. All three have begun to reconsider their defence strategies. 

Japan has raised its defence budget to levels not seen since the Second World War. South Korea is debating whether it needs its own nuclear weapons to counter the North. 

According to Dr Howell, South Korea’s worries are valid, taking into account the rhetoric that has come out of Pyongyang in recent years. He said: ‘Even though Kim abandoned the reunification of the Korean Peninsula as a goal, in January 2024, he did not rule out North Korea’s intention to absorb, subjugate, and annexe South Korea in the event of any war.’

China, which once acted as a buffer, no longer looks able or willing to restrain Kim’s ambitions. 

The United States continues to promise nuclear protection to its allies, but a larger North Korean arsenal complicates any response plan. Despite Trump’s previous strongly worded warnings, no military commander wants to face a leader who believes he can fire multiple warheads and survive the retaliation.

Kim Jong-un overseeing tests for a new multiple rocket launcher in September last year. Analysts say he will not hesitate to use his nuclear weapons at the start of a conflict

Kim inspecting an operational army base in 2024. Dr Howell says he is determined not to give away his nuclear weapons

Read More

North Korea has long-range missiles that ‘pose nuclear threat to the continental US’

Beneath all these strategic considerations lies the simple human cost of living next to a nuclear factory that never sleeps. The workers who build, reprocess and handle nuclear material do so in conditions that remain unknown. 

Accidents inside the complex would never be reported, and radiation leaks would be hidden from the outside world. The region surrounding Yongbyon sits on land that could one day become heavily contaminated. 

For the people who live near the complex, the threat is not only a distant missile strike but immediate exposure to the byproducts of bomb production. 

A North Korean defector claimed last year that children were being born without anuses, toes, or hands as a mysterious illness spread near the Punggye-ri test site, raising fears of what could happen to those living near nuclear production sites. 

The truth is that the world now faces a North Korea that cannot be forced back to the negotiating table with the old methods. Sanctions and diplomatic pressure have failed. 

Every year that passes without a new agreement allows Yongbyon to grow larger. Every month of construction feeds a programme that is now too big to dismantle quickly. 

What began as a secret project decades ago is now a visible nuclear empire, captured in satellite imagery that shocks even seasoned analysts.

And if nothing changes, the outcome is clear – North Korea will move from a state with nuclear weapons to a state defined by them. 

As Kim continues to build his weapons, Dr Howell believes that he has a clear strategy to reach his objectives. 

He explained: ‘Thanks to North Korea’s cooperation with Russia, Kim Jong Un is now more emboldened than ever, able to play off Russia and China, as well as the US, in order to ensure he obtains his goal of recognition of North Korea as a nuclear-armed state.

‘At present, North Korea has an estimated 50 warheads, but if current levels continue, North Korea could possess between 200-250 warheads at least by 2030. ‘The modernisation of its capabilities and the development of a new uranium enrichment plant only evince Kim’s statements earlier this year with respect to accelerating North Korea’s quest both to modernise and expand its nuclear development.’