Nine countries own nuclear weapons - United States, Great Britain, Francuska, Israel, Rusija, China, North Korea, Indija i Pakistan - and almost all continued intensive modernization programs during 2024, upgrading existing weapons and adding newer versions, it says Deutsche says.
This is one of the key findings from the 2025 report of the Stockholm International Peace Research Institute (SIPRI).
Ninety percent of the nuclear potential - two countries
SIPRI researchers conclude that of the total estimated 12.241 are nuclear warheads in January 2025, about 9.614 were either in military stockpiles: either mounted on missiles, or housed at bases with operational forces, or in central depots from which they could be deployed.
Estimates say that about 3.912 of those warheads were deployed on missiles and aircraft, and about 2.100 of them were in a state of high combat readiness on ballistic missiles.
Almost all of those warheads, about 90 percent, belong to Russia or the US, but it is estimated that China may also now have some warheads on missiles.
SIPRI analysts warn that more states are considering developing or deploying nuclear weapons, amid renewed national debates about nuclear status and strategy.
This includes new agreements on the deployment of nuclear weapons: Russia claims to have deployed nuclear weapons on the territory of Belarus, while some NATO members in Europe have shown their willingness to host American nuclear weapons.
The bottom line is this: the world's nuclear arsenals are increasing and improving. SIPRI estimates that China now has at least 600 nuclear warheads and that its arsenal is growing faster than that of any other country.
During 2024, India is believed to have slightly expanded its nuclear arsenal, while Pakistan continued to develop new systems for the use of nuclear weapons - that is, missiles and other military platforms with which nuclear warheads can be launched at targets. At the same time, he continued to accumulate fissile material, which is the key raw material for the production of nuclear weapons.
Israel, which carried out attacks on Iran's nuclear facilities on June 13, killing military leaders and nuclear scientists, continues to withhold information about its own nuclear capabilities. However, it is believed to be in the process of modernizing its arsenal as well as upgrading its plutonium production facility in the Negev desert.
The end of nuclear disarmament - after the collapse of the USSR
In the mid-1980s, the number of nuclear warheads, bombs and shells in the world was much higher than it is now - about 64.000.
Since the collapse of the Soviet Union in 1991 and the end of the Cold War, the dismantling of decommissioned warheads, those removed from the nuclear arsenal, has proceeded faster than the deployment of new ones.
However, judging by the latest assessment, that trend seems to have reversed. "Our biggest concern is that the long-term reduction in the number of nuclear warheads is coming to an end," SIPRI director Dan Smith told DW.
International security has been deteriorating for more than a decade
Although it is a common practice for states that possess nuclear weapons to modernize and improve their capabilities, Smith says that the strengthening of that process occurred at the end of the second term of former US President Barack Obama (from 2013 to January 20, 2017) with greater investments in new generations of missiles and carriers.
"Already a few years before that, the security horizon in the world had begun to darken, and the states with nuclear weapons had already begun to introduce processes that we could call 'intensive' modernization, so not just a little tweaking, but serious and big changes," Smith said.
In 2007, Russian President Vladimir Putin gave a speech at the Munich Security Conference in which he sharply criticized the US-dominated world order, NATO's eastward expansion and the approach to disarmament, which, in his opinion, threatened Russian security.
But just two years later, in 2009, Barack Obama announced the goal of complete nuclear disarmament in Prague. "The existence of thousands of nuclear warheads is the most dangerous legacy of the Cold War," he said at the time.
He added that the US will "take concrete steps towards a world without nuclear weapons" and that it will negotiate a new Strategic Arms Reduction Treaty (New START) with Russia. That agreement was signed and entered into force in 2011.
Russia's invasion of Ukraine
However, following the Russian invasion of Ukraine in February 2022, the Biden administration released a 2022 nuclear strategy that identified the modernization of the US nuclear arsenal as one of its top priorities.
In February 2023, President Putin signed a law suspending Russia's participation in the New START treaty.
"The wave of insecurity has been slowly building since 2007-08, through 2014, until it started to come crashing down in February 2022. I think that's when many ordinary citizens became aware of a deterioration that had already been going on for more than a decade," Smith said.
Artificial intelligence and new technologies increase the risk of nuclear war
In the introduction to SIPRI's 2025 report, Smith warns of the possibility of a new nuclear arms race that carries "much more risk and uncertainty" than during the Cold War — primarily due to artificial intelligence and new technologies in the areas of cyber capabilities and space systems.
"The coming nuclear arms race will be as much about artificial intelligence, cyberspace and space as it is about missiles in bunkers, on submarines or bombs on airplanes. It will be as important software as hardware," Smith said.
This further complicates the issue of how to control and monitor nuclear weapons and stockpiles, as competition among nuclear powers has previously been largely a matter of numbers.
There has long been a debate about artificial intelligence in the context of so-called "killer robots" (lethal autonomous weapon systems), and since the beginning of the Russian invasion of Ukraine, the use of automated and semi-automated drones — but not so much in relation to nuclear weapons.
Who will play the role of Colonel Petrov?
Artificial intelligence makes it possible to process vast amounts of information extremely quickly, and in theory this should help decision makers react more quickly.
However, if there is an error in the software or in a system that relies entirely on LLM-, machine learning and artificial intelligence, even a small technical failure could potentially lead to a nuclear attack.
"I think there has to be a red line that probably all political and military leaders will agree on — that the decision to launch a nuclear weapon must not be made by artificial intelligence," Smith said, recalling Soviet Lt. Col. Stanislav Petrov.
In 1983, Petrov was on duty at the Soviet nuclear early warning command center, 100 kilometers south of Moscow, when the system reported the launch of one intercontinental ballistic missile from the US, followed by four more. Fortunately, Petrov thought it was a false alarm and decided not to pass the information immediately up the chain of command—a decision that likely prevented a nuclear retaliatory attack, and at worst, all-out nuclear war.
"I guess the big question is: Who in the world of artificial intelligence will have the role of Lt. Col. Petrov?" Smith asked.
Source: Deutsche Welle
