China's nuclear arsenal increasing: SIPRI

The nine nuclear-armed states, including the US, Russia, the UK, France, China, India and Pakistan, continue to modernise their nuclear arsenals, leading Swedish think-tank SIPRI said on Monday.

Several nuclear-armed states deployed new nuclear-armed or nuclear-capable weapon systems in 2022, the Stockholm International Peace Research Institute (SIPRI) said in its yearbook.

According to the Swedish watchdog's estimate, the size of China's nuclear arsenal increased from 350 warheads in January 2022 to 410 in January 2023 and the report said it is expected to keep growing.

"Depending on how it decides to structure its forces, China could potentially have at least as many intercontinental ballistic missiles (ICBMs) as either the USA or Russia by the turn of the decade," it said.

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The SIPRI said India and Pakistan appear to be expanding their nuclear arsenals, and both countries introduced and continued to develop new types of nuclear delivery systems in 2022.

"China has started a significant expansion of its nuclear arsenal," 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).

While Pakistan remains the main focus of India's nuclear deterrent, India appears to be placing growing emphasis on longer-range weapons, including those capable of reaching targets across China, the report said.

"The nine nuclear-armed states -- the United States, Russia, the United Kingdom, France, China, India, Pakistan, the Democratic People's Republic of Korea (North Korea) and Israel -- continue to modernise their nuclear arsenals and several deployed new nuclear-armed or nuclear-capable weapon systems in 2022," the SIPRI said.

"Of the total global inventory of an estimated 12,512 warheads in January 2023, about 9,576 were in military stockpiles for potential use -- 86 more than in January 2022," it said.

"Of those, an estimated 3,844 warheads were deployed with missiles and aircraft, and around 2,000 -- nearly all of which belonged to Russia or the US -- were kept in a state of high operational alert, meaning that they were fitted to missiles or held at airbases hosting nuclear bombers," the SIPRI said.

It said Russia and the US together possess almost 90 per cent of all nuclear weapons.

The sizes of their respective nuclear arsenals seem to have remained relatively stable in 2022, although transparency regarding nuclear forces declined in both countries in the wake of Russia's invasion of Ukraine in February 2022, the report said.

"In addition to their useable nuclear weapons, Russia and the USA each holds more than 1,000 warheads previously retired from military service, which they are gradually dismantling," it said.

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The report said nuclear arms control and disarmament diplomacy suffered major setbacks following Russia's full-scale invasion of Ukraine in February 2022.

"We are drifting into one of the most dangerous periods in human history," said SIPRI director Dan Smith.

"It is imperative that the world's governments find ways to cooperate in order to calm geopolitical tensions, slow arms races and deal with the worsening consequences of environmental breakdown and rising world hunger," he said.