Nuclear arms race: China expands its arsenal fastest, SIPRI report reveals

Last year, nearly all 9 nuclear-armed states continued modernization programs. Currently, China is expanding its arsenal the fastest, while Russia and the U.S. collectively possess about 90% of nuclear stockpiles, but their programs faced issues. This was reported in the new report by the Stockholm International Peace Research Institute (SIPRI).

Almost all 9 nuclear states—the United States, Russia, China, the United Kingdom, France, Pakistan, India, North Korea, and Israel—continued to modernize their weapons and develop new versions in 2024.

As of January 2025, out of a total global arsenal of 12,241 warheads, 9,614 were in military stockpiles for potential use.

"An estimated 3912 of those warheads were deployed with missiles and aircraft and the rest were in central storage. Around 2100 of the deployed warheads were kept in a state of high operational alert on ballistic missiles. Nearly all of these warheads belonged to Russia or the US," the report states.

Development pace of nuclear countries' programs

The United States and Russia collectively own about 90% of the world’s nuclear weapons. Their military stockpiles remained relatively unchanged in 2024; however, both Moscow and Washington are implementing modernization programs to increase their arsenals.

SIPRI writes that the U.S. nuclear weapons program is progressing, but experienced funding and planning issues last year that could delay the production of new weapons and significantly increase costs.

Meanwhile, the Russian nuclear modernization program also faced problems. Last year, the country failed to successfully test the Sarmat intercontinental ballistic missile (ICBM) and delayed system upgrades. Moscow has also yet to increase the number of non-strategic warheads, a goal it had set for 2020.

In contrast, China is expanding its nuclear arsenal the fastest—by approximately 100 warheads per year since 2023—more rapidly than any other country. Currently, Beijing is estimated to possess at least 600 nuclear warheads.

It is noted that by 2035, China could increase its stockpile to 1,500 warheads, although that would still constitute about one-third of the arsenals of Russia and the United States.

The United Kingdom is facing financial challenges in increasing its nuclear weapons stockpile, while France is developing new cruise missiles and submarines.

At the same time, India slightly expanded its nuclear arsenal in 2024 and continued developing new delivery systems. Pakistan also worked on these systems and accumulated fissile materials.

North Korea assembled about 50 warheads last year and possesses enough fissile material to produce another 40.

Israel is also believed to be modernizing its nuclear potential, although it does not publicly acknowledge the existence of such weapons. Last year, the country tested a missile engine potentially linked to Jericho-type nuclear ballistic missiles and is likely upgrading the plutonium production reactor in Dimona.

SIPRI Director Dan Smith warns about the challenges facing nuclear arms control and the prospects of a new nuclear arms race. Smith observes that "bilateral nuclear arms control between Russia and the USA entered crisis some years ago and is now almost over".

"The era of reductions in the number of nuclear weapons in the world, which had lasted since the end of the cold war, is coming to an end," said Hans M. Kristensen, Associate Senior Fellow with SIPRI’s Weapons of Mass Destruction Programme and Director of the Nuclear Information Project at the Federation of American Scientists (FAS). "Instead, we see a clear trend of growing nuclear arsenals, sharpened nuclear rhetoric and the abandonment of arms control agreements."