According to the Stockholm International Peace Research Institute (SIPRI) Yearbook 2025, China has rapidly increased its nuclear arsenal to at least 600 warheads, a rise of 100 warheads in 2023 and 2024, indicating that the world is entering a dangerous new phase of nuclear competition. With this acceleration, China is now the nuclear power with the quickest rate of growth, surpassing all other nuclear-armed nations.
Nearly all nine nuclear-armed states—the US, Russia, the UK, France, China, India, Pakistan, North Korea, and Israel—continued to modernize their nuclear forces vigorously in 2024, introducing new delivery systems and upgrading their current weapons, according to SIPRI’s annual assessment. The research cautions that the period of worldwide nuclear arsenal reductions, which has continued since the conclusion of the Cold War, is coming to an end and that arms control institutions are seriously weakened.
As of January 2025, there were an estimated 12,241 nuclear warheads in the world, of which 9,614 were in military stocks for possible deployment and 3,912 were mounted on airplanes or missiles. Almost all of them, about 2,100 of which are on high operational alert, are owned by the US or Russia, though it is now thought that China keeps some warheads on missiles in peacetime. With 5,459 warheads in Russia’s arsenal and 5,177 in the US, the two countries still own roughly 90% of the world’s nuclear weapons, but China’s stockpile is expanding at a never-before-seen pace.
According to SIPRI data, China had built or was almost finished building over 350 additional intercontinental ballistic missile (ICBM) silos in the country’s eastern mountain regions and northern desert regions by January 2025. By the end of the decade, China might have as many ICBMs as the US or Russia if current trends continue, and it might have 1,000 warheads in seven or eight years. China’s arsenal would still only be around one-third the size of the present US and Russian arsenals, even if 1,500 warheads were predicted to be available by 2035.
The modernization of other nuclear powers is also underway. With India’s arsenal increasing to roughly 180 warheads and Pakistan’s staying stable at about 170, both countries are creating new delivery mechanisms. With enough fissile material, North Korea could potentially double its estimated 50 weapons. Israel’s arsenal still stands at roughly 90 warheads, while the UK and France are maintaining or intending to increase their arsenals.
The rapid advancement of technologies like artificial intelligence, cyber capabilities, missile defense, and quantum computing, which are fundamentally redefining nuclear deterrence and raising the possibility of instability and miscalculation, further increases the risks of a new nuclear arms race, according to SIPRI Director Dan Smith. These risks are made worse by the deterioration of arms control accords, especially as the US-Russia New START pact approaches its 2026 expiration date with no replacement in sight.
According to the report’s conclusion, the post-Cold War trend of shrinking nuclear arsenals is coming to an end and is being replaced by a new period of modernization, expansion, and increased nuclear hazards. China’s quick build-up is a major factor in this new arms race.
