Russia is amending its doctrine on the use of nuclear weapons as a response to perceived Western involvement in the Ukraine war, its Deputy Foreign Minister Sergei Ryabkov was quoted as saying on Sunday.

The comments came at a time when Russia is battling an incursion into its Kursk region by Ukrainian troops and amid growing attacks on Russian territory by Kyiv using Western weapons.

So what exactly is Russia’s nuclear doctrine, how big is its arsenal, what might change, and are others changing their policies too?

What is Russia’s nuclear doctrine?

Russian President Vladimir Putin last signed off on the country’s nuclear doctrine in June 2020. The six-page doctrine is formally called the Basic Principles of State Policy on Nuclear Deterrence.
It says Russia considers nuclear weapons to be exclusively a means of deterrence.
The doctrine deems the use of nuclear weapons an “extreme and compelled measure”.
It emphasises deterrence of aggression by the Russian military strength, “including its nuclear weapons”.
Under the doctrine, Russia can use nuclear weapons in “response to the use of nuclear and other types of weapons of mass destruction against it and/or its allies”.
Additionally, it can use them in case of aggression against Russia with conventional weapons “when the very existence of the state is in jeopardy”.

Why is Russia changing its nuclear doctrine?

Minister Ryabkov said the decision to change the nuclear doctrine is “connected with the escalation course of our Western adversaries”.

In late August, Ukraine confirmed it had used weapons supplied by the United States in its Kursk incursion.

Russia’s Sunday announcement is “not an isolated instance”, Keir Giles, a senior consulting fellow of the Russia and Eurasia Programme at the London-based Chatham House think tank, told Al Jazeera.

Instead, Giles said, it is “part of the ongoing Russian campaign that has shaped the US course of action throughout this war” against Ukraine.

Has Putin issued nuclear warnings before?

In February 2022, Russia launched a full-scale invasion of Ukraine. Since then, the Kremlin has repeatedly used threats and rhetoric that experts say is aimed at deterring Western intervention in the war.

In March 2023, the United Nations Security Council warned that the risk of the use of nuclear weapons was higher than at any time since the Cold War.

Putin has made several implicit threats of nuclear attack since the war broke out:

On February 24, 2022, when he announced the special military operation in Ukraine, he said Russia possesses certain advantages in the newest types of weaponry. “Whoever tries to hinder us, or threaten our country or our people, should know that Russia’s response will be immediate and will lead you to consequences that you have never faced in your history,” he added.
In September 2022, Putin said, “If the territorial integrity of our country is threatened, we will without doubt use all available means to protect Russia and our people – this is not a bluff.” A few days later, he said the US set a precedent when it dropped two atomic bombs on Japan in 1945.
In February 2023, Russia said it would suspend its participation in the New START treaty with the US, which limits the number of nuclear warheads each side can deploy.
In March 2023, Russia said it struck a deal with its ally Belarus, which shares a border with Ukraine, to station tactical nuclear weapons there. Tactical nuclear weapons are used in the battlefield including in proximate fighting, unlike strategic weapons which are meant to be propelled over long distances to destroy enemy cities.
In October 2023, Putin said there was no need to amend its nuclear doctrine because if another country attacked it with nuclear weapons, Russia would respond within a split second with hundreds of nuclear weapons. “I think, no person of sound mind and clear memory would think of using nuclear weapons against Russia.”
In February 2024, Putin took a short flight on a modernised Tu-160M nuclear-capable strategic bomber. A few days later, he warned Western countries that they risked provoking nuclear war if they sent troops to fight in Ukraine.
In March 2024, when Putin was asked in an interview whether Russia was ready for nuclear war, he responded: “From a military-technical point of view, we are, of course, ready.” However, he added that Russia has never felt the need to use nuclear weapons in Ukraine.

Russia’s intimidation tactic seems to have worked, say analysts. While Ukraine has used US weapons in its Kursk incursion, it was “careful not to tell the US in advance because they were scared the US would try to stop it”, Giles said.

He added that US restrictions on Ukraine using long-range missiles in Russia are also possibly because Washington is scared of risking a nuclear war.

What changes could Russia make to the doctrine?

That remains a mystery. And that is likely how Russia wants to keep it, say experts — ambiguous.

In theory, Russia could lower the threshold at which it might use nuclear weapons, a bar currently set for either nuclear attacks on its territory or conventional attacks that threaten its existence or sovereignty as a state.

Giles explained that Russia’s nuclear doctrine has a published aspect and a secret, classified aspect. The Kremlin could possibly amend the secret part, he added.

“Russia wants the world to think that it is at a nuclear hair trigger and that anything could cause nuclear war,” he said.

Which countries have nuclear weapons?

The total global stockpile of nuclear weapons comprises more than 12,000 warheads owned by nine countries.

Russia has nearly 6,000 warheads, some stationed in Belarus. The US owns a little more than 5,000, some stationed in Italy, Turkey, Belgium, Germany and the Netherlands.

China, France, the United Kingdom, Pakistan, India, Israel and North Korea also have nuclear weapons.

Which other countries have changed or debated their nuclear policy recently?

North Korea legislated nuclear posture in 2013 and 2022. The 2013 law decreed that North Korea would not attack with nuclear weapons first, but would retaliate with nuclear weapons even if a nuclear power attacked with conventional weapons. The 2022 law stated that North Korea could attack not only when an attack actually took place, but also when it judged an attack was imminent.
In August 2019, Defence Minister Rajnath Singh signalled a change to India’s nuclear doctrine by saying it might reconsider its No First Use (NFU) policy, which decrees that the nuclear power will not use nuclear weapons unless it is in retaliation against another country using nuclear weapons. However, India is not known to have formally changed its doctrine.
China dropped NFU from its formal position in October 2023, though officially it has not said so. China was the first nuclear state to pledge NFU unilaterally in 1964, and it maintained its pledge formally for decades since.
In May 2024, Khalid Ahmed Kidwai, adviser to Pakistan’s National Command Authority (NCA), which is in charge of the country’s nuclear weapons programme, said during a seminar that Islamabad “does not have a No First Use policy”. Pakistan has never published a clear nuclear doctrine, and Kidwai’s comment was the clearest indication yet that Islamabad is open to using tactical nuclear weapons.