The nine states that have nuclear arsenals are strengthening them amid the armed conflict in Ukraine and the wider deterioration of the global security situation, the Swedish think tank Stockholm International Peace Research Institute (SIPRI) points out today.

The global stockpile of nuclear warheads fell by nearly 200 to about 12,512 from early 2022 to early 2023, SIPRI notes in its annual report released today. But the number of nuclear weapons classified as operational, i.e. ready to be used, increased by 86, to an estimated 9,576.

Not only do “global reductions in operational nuclear warheads appear to have frozen” but “their numbers are increasing again,” the institute’s researchers warn.

“At the same time, both the US and Russia have embarked on extensive and expensive programs to replace and modernize their nuclear warheads, the missiles, aircraft and submarines capable of launching them, and their nuclear weapons production facilities.”

For decades, the number of nuclear weapons has been steadily declining. However, the decrease was mainly due to the destruction of decommissioned nuclear warheads by Russia and the US.

Researchers emphasize operational arsenals. As SIPRI reminds, in addition to Russia and the USA, China, France, Britain, Pakistan, India, Israel and North Korea have such.

As geopolitical tensions continue, especially after Russia’s military invasion of Ukraine, the institute expresses its strong concern (again) this year.

“Most nuclear-weapon states are hardening their rhetoric about the importance of nuclear weapons, and some have gone so far as to directly or indirectly threaten their potential use,” said Matt Korda, one of the report’s authors. “This increased competition over nuclear weapons has dramatically escalated the risk that they will be used, for the first time since World War II.”

Worse, diplomatic efforts to reduce nuclear arsenals have been dealt a heavy blow since Russia invaded Ukrainian territory in February 2022.

Russian President Vladimir Putin suspended New START – the only major US nuclear arms control agreement remaining in force – in February 2023.

In addition, negotiations to reinstate the international agreement on Iran’s nuclear energy program, officially the Joint Comprehensive Plan of Action (JCPOA), have been sidelined and overshadowed by Tehran’s support for Moscow and the political situation in the Islamic Democracy. A successful outcome of the effort to bring the parties back into full compliance appears unlikely, SIPRI finds.

Russia and the US are by far the states with the largest arsenals: together, they possess about 90% of nuclear warheads. China has long occupied third place.

Most of the increase in operational warheads came from China, which went from 350 to 410. Beijing is investing heavily in its military as the Chinese economy and Chinese influence grow, according to SIPRI director Dan Smith.

“China has begun a significant expansion of its nuclear arsenal,” also points out Hans M. Christensen, one of the report’s editors, for whom it seems “difficult” to reconcile this trend with China’s “stated goal of simply having the minimum nuclear forces necessary to defend its national security.”

India, Pakistan and North Korea also increased their arsenals, as did Russia, to a lesser extent (from 4,477 to 4,489 warheads), while the other nuclear-armed powers maintained their stockpiles.

Mr. Smith notes that, however, the global nuclear arsenal is still far below the 1980s, when it exceeded 70,000 warheads.

For him, the increase in stocks cannot be explained simply by the war in Ukraine, taking into account factors such as the time required for their development and the fact that most countries that made this choice are not directly affected by the armed conflict.