The Stockholm International Peace Research Institute (SIPRI) released its Yearbook 2025 on June 16, offering a comprehensive assessment of global nuclear forces. The report highlights that China’s nuclear arsenal is expanding at a rapid pace. The SIPRI estimates that the number of Chinese nuclear warheads increased from 500 in January 2024 to approximately 600 by January 2025. Since 2023, China has been adding approximately 80-100 warheads annually, and this growth is expected to continue in the coming decades. This makes China’s nuclear arsenal the fastest-growing in the world.
Similarly, a report from the Bulletin of Atomic Scientists also claimed that China’s nuclear arsenal is expanding more rapidly than any of the other eight nuclear-armed states. The report estimated China has approximately 600 nuclear warheads. To accommodate its growing arsenal, China constructed three new intercontinental ballistic missile (ICBM) silo fields in 2024.
Last year, the U.S. Department of Defense’s annual report on Chinese military power also estimated that China has more than 600 operational warheads and is projected to have over 1,000 nuclear warheads by 2030.
As per the latest SIPRI report, China is building new ICBM silos at six separate locations: three in northern China and three in mountainous areas of central China. The report noted that China is creating approximately 350 new ICBM silos, which could allow it to match the ICBM numbers of Russia or the United States by the end of the decade. The northern sites may have been chosen for their strategic advantage, offering greater protection against long-range conventional attacks. Although some missiles are believed to have been loaded into the silos, it is still uncertain whether any of them have become fully operational.
The exact yields of China’s nuclear warheads remain uncertain. Older missiles likely carried high-yield warheads in the megaton range. Newer long-range systems are believed to use warheads in the few-hundred-kiloton range, possibly including low-yield variants.
China’s nuclear arsenal includes land-based missiles and dual-capable systems like the DF-26. About half of the DF-26 missiles are believed to carry conventional warheads. In addition to its land-based expansion, China is enhancing its sea-based nuclear deterrent by upgrading its Type 094 ballistic missile submarines with longer-range JL-3 submarine-launched ballistic missiles (SLBMs). China already operates six nuclear-powered ballistic missile submarines (SSBNs), capable of launching 72 SLBMs. The older JL-2 missiles on these submarines are being replaced with longer-range JL-3 missiles. The JL-3 will also be used on future submarines like the Type 096.
China is also developing a new class of submarines and strategic bombers, reflecting a move toward a more advanced and diversified nuclear force. According to SIPRI, approximately 132 of China’s warheads are thought to be in storage, likely meant for new missile systems that are nearly ready for deployment.
China has traditionally kept its nuclear warheads stored separately from its delivery systems, but recent assessments indicate that this practice may be changing. Some warheads are now believed to be mounted on missiles even during peacetime, suggesting a shift from China’s long-standing policy of maintaining a demated posture.
This shift in China’s nuclear posture likely reflects changing strategic priorities. Hans Kristensen, associate senior fellow at SIPRI, noted that the rapid buildup may be driven by a view that “minimum deterrence” is no longer sufficient, especially given President Xi Jinping’s goal of creating a “world-class military” and growing concerns over the effectiveness of China’s retaliation against advanced U.S. missile defense systems.
While responding to a question about the SIPRI report, Chinese Foreign Ministry spokesperson Lin Jian dismissed the concern about nuclear buildup and reiterated that China follows a “no first use” policy and maintains the minimum level of nuclear arsenal for national security. Lin argued that instead of China, the focus should be on the United States’ extensive nuclear modernization and extended deterrence. Some Chinese experts argue that the SIPRI data is affected by the “Western narrative” that exaggerates the “China threat.” According to them, the intention is to push Beijing into nuclear disarmament talks, which China is unlikely to participate in as its warhead counts remain far below either the United States’ or Russia’s.
Based on the SIPRI report, there are 12,241 nuclear warheads worldwide as of January 2025, with 9,614 in military stockpiles. Of these, approximately 3,912 warheads are deployed on missiles or aircraft. Approximately 2,100 of the deployed warheads are maintained on high operational alert, nearly all belonging to the U.S. and Russia. Together, these two countries constitute approximately 90 percent of the world’s nuclear arsenal.
There are global trends toward more competitive and less constrained nuclear environments. The nuclear armed countries are modernizing their forces and moving away from the long-standing disarmament effort. For example, the U.S. plans to spend approximately $1.7 trillion over the next 30 years on its nuclear arsenal modernization, for an average cost of $75 billion annually between 2023 and 2032. To put that in perspective, even after adjusting for inflation, the U.S. is spending more than double the annual cost of the Manhattan Project. Last year, Russia also revised its nuclear doctrine, which lowered the nuclear threshold and expanded the role of nuclear weapons in non-nuclear threats.
Similarly, under its Strategic Defense Review 2025, the United Kingdom is proactively investing in nuclear modernization. It plans to invest 15 billion pounds in the nuclear warhead program to modernize its submarine fleet.
The SIPRI report estimates that North Korea has assembled approximately 50 nuclear warheads and possesses enough fissile material to produce 40 more. North Korean leader Kim Jong Un openly calls for the “limitless” expansion of nuclear weapon programs. Last year, South Korean officials warned that Pyongyang was nearing completion of tactical nuclear weapon development.
In the South Asian region, India possesses approximately 180 nuclear warheads, slightly more than Pakistan’s 170. In their conflict in early May 2025, the risk of escalation from conventional to nuclear warfare increased due to the spread of misinformation.
While India and Pakistan have near nuclear parity, the gap between India and China is significant, with China holding more than three times the total warhead of India. This gap put extra pressure on India to increase deterrence through strengthening sea-based capabilities.
Today’s changing geopolitical landscape helps explain the global shift toward nuclear expansion and away from arms control treaties. Most major arms control agreements emerged during the Cold War, a period defined by a clear bipolar balance of power and threat. In contrast, the current global environment is far more complex and fluid, with multiple actors and overlapping security concerns. As a result, existing norms no longer function effectively – for example, the U.S. has withdrawn from arms control treaties reached with Russia by pointing to China’s absence from such arrangements – and new rules have yet to take shape. This uncertainty fuels a sense of strategic insecurity, contributing to the global nuclear modernization and expansion trend.