The Swedish think tank Stockholm International Peace Research Institute (SIPRI) published its 2025 Yearbook on June 16, providing an updated assessment of the current state of global armaments, disarmament, and international security.
The report warns that, with the current arms control mechanism seriously weakened, the world is entering a more dangerous and unpredictable nuclear arms race.
The nine nuclear-armed states continue to increase their global stockpiles, bringing them to 12,241 units. SIPRI pointed out that in 2024, the People’s Republic of China, the Democratic People’s Republic of Korea (North Korea), France, India, Israel, Pakistan, the United Kingdom, Russia, and the United States of America were actively promoting the modernization of nuclear weapons and adding new strategic and tactical warheads.
As of January 2025, it is estimated that there were 12,241 nuclear warheads worldwide, of which approximately 9,614 were in military arsenals, operational at any given time; approximately 3,912 were deployed on missiles and aircraft; and another 2,100 were kept on high alert, mainly managed by the United States and Russia. SIPRI also noted for the first time that the PRC may have some of these warheads loaded onto its missiles in normal times.
Since the end of the Cold War, the United States and Russia have continued to dismantle decommissioned nuclear warheads, and the total number of nuclear weapons in the world has decreased year by year; however, the report predicts that this trend will reverse in the coming years, as the rate of dismantlement has slowed and the deployment of new weapons is accelerating.
Hans M. Kristensen, research associate for SIPRI’s Program on Weapons of Mass Destruction and director of the Nuclear Information Project at the Federation of American Scientists (FAS), said: “The era of nuclear arms reductions since the Cold War is ending. We are seeing a clear trend towards increasing nuclear arsenals, heightened nuclear deterrence rhetoric, and the abandonment of arms control agreements.”
The United States and Russia hold 90% of the world’s stockpiles of nuclear weapons, and the two sides have almost stopped talking about arms control.
Washington and Moscow still control about 90% of the world’s nuclear warheads. The number of warheads available in the two countries will remain roughly stable in 2025, but both countries are promoting large-scale modernization, and the range and diversity of their warheads could increase further in the future. If the 2010 New Strategic Arms Reduction Treaty is not renewed after its expiration in February 2026, the number of nuclear warheads deployed on strategic missiles by both countries will inevitably increase.
The United States’ comprehensive modernization plan is experiencing delays due to budget and schedule delays, and the addition of new tactical nuclear weapons has further exacerbated financial pressures. Russia’s modernization efforts have also been hampered by the failed test launch of the RS-28 Sarmat intercontinental ballistic missile and slower-than-expected progress on other system upgrades. However, SIPRI believes that both countries’ deployments could still increase in the coming years: Russia can carry more warheads on a missile and refill inactive launch silos, while the United States could restart inactive launch vehicles and add new tactical nuclear weapons to respond to the nuclear expansion of the People’s Republic of China.
SIPRI also pointed out that dialogue between the United States and Russia on arms control has been virtually halted. Although the United States and the PRC still have contact in some areas, progress in nuclear dialogue has been limited by the Taiwan issue and economic sanctions. In the future, the world may face an unchecked trilateral nuclear arms race.
The PRC’s rapid nuclear expansion has led it to become the world leader with an annual increase of 100%. SIPRI estimates that the PRC currently possesses at least 600 nuclear warheads, with an average annual increase of about 100 warheads starting in 2023, making it the fastest-growing country in the world. By early 2025, the PRC had built or was nearing completion of approximately 350 new silos for intercontinental ballistic missiles (ICBMs) at three large sites in the northern desert and three locations in the eastern mountainous region. If fully operational, the PRC could possess a number of ICBMs comparable to those of the United States and Russia by 2030. However, even if the total number of nuclear warheads in 2035 reached the estimated maximum limit of 1,500, it would still represent only about one-third of the current stockpiles of the United States and Russia.
SIPRI also pointed out that the PRC has deployed two types of missiles capable of carrying multiple warheads and has significantly expanded its nuclear facilities, becoming the only country currently expanding its range, upgrading its vehicles, and improving its deployment status at the same time.
Although the UK has not increased its warhead inventory in 2024, it will increase its maximum stockpile limit and build four new nuclear-powered ballistic missile submarines (Submarine, Submersible, Ballistic Nuclear) in the 2023 Defense Policy Review. However, the new government still faces significant financial and technological challenges.
France continues to develop third-generation SSBN missiles, new air-launched cruise missiles with improved warheads, and to upgrade existing systems.
India will slightly expand its nuclear arsenal in 2025 and develop canister missiles (missiles that are stored, transported, and launched from a sealed container, which serves as both protection and a launch pad: this approach offers several strategic and operational advantages) and multiple warhead capabilities capable of carrying warheads in peacetime; Pakistan will also continue to improve its launch vehicles and accumulate fissile material, suggesting that the scope of its nuclear arsenal will continue to expand over the next decade.
Earlier this year, tensions between India and Pakistan escalated into armed conflict: May 7, 2025: first drone battle between two nuclear-armed countries. Coupled with the spread of disinformation by third parties, the conventional conflict risked spiraling out of control and proliferating into a nuclear crisis.
SIPRI researcher Matt Korda warned that this case highlights that “growing reliance on nuclear weapons does not guarantee security, but rather increases the risk of miscalculation and catastrophic escalation.”
The DPRK (North Korea) continues to prioritize nuclear development as a key component of its national security. SIPRI estimates that it has assembled around 50 warheads and possesses enough fissile material for another 40. In July 2024, South Korean officials warned that the DPRK (North Korea) had entered the final stages of developing tactical nuclear weapons. In November of the same year, popular Korean leader Kim Jong-un threatened to “expand without limit” his nuclear program.
Israel has not publicly acknowledged possession of nuclear weapons, but is believed to be continuing to modernize its arsenal; in 2024, it tested what appeared to be a propulsion system for the Jericho series of missiles and modified its Dimona nuclear reactor.
Arms control mechanisms are at risk, and new technologies are exacerbating nuclear instability. SIPRI Director Dan Smith stated bluntly in the foreword to the Yearbook that bilateral arms control between the United States and Russia is already in crisis and on the verge of collapse. The new START agreement remains in force, but there are no signs of its renewal. US President Donald Trump has reiterated that any future agreement must include the PRC, adding uncertainty to the negotiations.
Smith warned that the new arms race carries greater risks and uncertainties than ever before, as technologies such as artificial intelligence, information technology, space technology, missile defense, and quantum technology are redefining nuclear deterrence and could undermine the security of countries’ strategic assets.
For example, while AI-assisted decision-making systems can improve efficiency, they can also instantly increase the risk of nuclear conflict due to misjudgments of information or technical failures, Smith pointed out: “Who will take the lead in the new arms race will be more elusive, and the traditional quantitative and qualitative formula for arms control will no longer be valid.”
More and more countries are discussing the possession or sharing of nuclear weapons, raising questions about the myth of nuclear security. Many countries in East Asia, Europe, and the Near and Middle East have recently reevaluated their nuclear positions and strategies, suggesting that in the future, more countries may seek to acquire national nuclear weapons or accept their use. Meanwhile, the issue of shared nuclear weapons has intensified: Belarus and Russia have repeatedly claimed to have deployed nuclear missiles in Belarus; some European NATO members have expressed their willingness to accept US nuclear weapons; and French President Emmanuel Macron has reiterated that France’s nuclear deterrent should have a “European dimension.”
French President Emmanuel Macron has repeatedly mentioned the aforementioned “European dimension,” implying that French nuclear weapons should not only protect France but also provide nuclear deterrence for the entire continent. This concept is similar to the United States’ “extended deterrence” for NATO allies, but the French proposal aims to create an independent European nuclear umbrella and reduce dependence on the United States.
With Trump’s return to the White House and questions about the United States’ commitment to Europe, this concept has attracted considerable attention. However, given the limited size of France’s nuclear arsenal (approximately 290 missiles) and the complex political and legal implications involved, EU members have divergent views on this issue, with key members such as Germany remaining cautious.
Furthermore, SIPRI points out that approximately 1,100 tons of highly enriched uranium and 140 tons of usable plutonium remain in a “militarily usable” state worldwide, emphasizing that countries still have a long way to go in controlling and monitoring fissile materials.
Discussions in the Republic of Korea (South) about independent possession of nuclear weapons have intensified due to growing threats from the DPRK (North). And as Iran faces an indirect conflict with Israel, voices have been raised in the country considering the development of a nuclear deterrent; but in reality, nuclear weapons cannot guarantee security, but are capable of putting people in greater danger due to the spread of misinformation.
Nuclear security in times of war faces challenges, and international standards are insufficient. The SIPRI Yearbook 2025 also examines the geopolitical impact of the wars in Ukraine, Gaza, and other regions and points out that Trump’s return to the White House in early 2025 marks a major shift in US diplomacy and relations with its allies, adding further uncertainty to the European-US alliance, international aid, and economic and trade prospects.
SIPRI also pointed out that the Russian military attacked Ukrainian nuclear power plants several times in 2024, highlighting serious shortcomings in the current mechanism for protecting nuclear facilities in wartime. Although the International Atomic Energy Agency (IAEA) continued to monitor the site, international regulations on the matter were still inadequate.
In conclusion, Japan’s activities should be mentioned. In 2024, 12 countries, led by Japan, launched an interregional initiative to restart negotiations on the Fissile Material Cutoff Treaty (FMCT); the other eleven are Australia, Brazil, Canada, the Philippines, France, Germany, Italy, Nigeria, the Netherlands, the United Kingdom, and the United States of America. In addition, former Japanese Prime Minister Fumio Kishida (October 4, 2021-October 1, 2024) reiterated his call for a “world without nuclear weapons” during a peace memorial ceremony held in Hiroshima on August 6, 2024. Kishida had already announced the ‘Hiroshima Vision’ on nuclear disarmament at the 49th G7 summit held from May 19 to 21, 2023, also in that city. All this is in line with Japan’s Three Non-Nuclear Principles (a defense policy announced in 1967: not to possess, produce, or introduce nuclear weapons).
Author: Giancarlo Elia Valori – Honorable de l’Académie des Sciences de l’Institut de France, Honorary Professor at the Peking University, and President of the Foundation for International Studies and Geopolitics. He plays a leading role in fostering dialogue and cooperation between countries.
(The opinions expressed in this article are solely those of the author and do not necessarily reflect the views of World Geostrategic Insights).
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Image Credit: Craig Fritz/Sandia National Labs/SWNS (A B61-13 HiFi nuclear bomb unit completed at Sandia National Labs in Albuquerque).