Seven weeks into Ukraine's incursion into Russia's Kursk Oblast, Russian President Vladimir Putin made a thinly veiled threat toward Ukraine and its allies during a Russian Security Council meeting on nuclear deterrence.
"An aggression by a non-nuclear state with the participation of a nuclear state is proposed to be considered as their joint attack on Russia," Putin said during the meeting on Sept. 25.
The Russian leader also suggested Russia may consider using nuclear weapons in case of a mass launch of drones or missiles crossing its border.
Russia also retains the right to use nuclear weapons in case of the event of an attack with conventional weapons that poses a critical threat to Russia and Belarus, Putin said, adding that these changes were made in agreement with Belarusian dictator Alexander Lukashenko.
Putin's comments came weeks after the Kremlin said Russia would be adjusting its nuclear weapons doctrine in response to what it described as the "challenges and threats, prompted by countries of the so-called collective West."
Accusing Western nations of "rejecting dialogue," ignoring Russia's security concerns, and inciting the war in Ukraine that Russia itself is waging, Kremlin spokesperson Dmitry Peskov said on Sept. 4 that such actions could not go unanswered.
"All of this is taken into account in Moscow, all of this is being analyzed and will lay the foundation for proposals (regarding the nuclear doctrine) that will be shaped," he said.
Peskov's comments are the latest instance of Russian nuclear rhetoric and saber-rattling, fueled in large part by developments during its full-scale invasion of Ukraine launched in February 2022.
Throughout the war, the Kremlin has repeatedly laid down red lines, the crossing of which it has said could provoke a nuclear response. Moscow’s intent of increasingly warning that it could resort to using nuclear weapons from its arsenal, the largest in the world, has been to deter Ukraine’s Western allies from further arming Kyiv.
Kyiv’s allies have gradually provided increasing amounts and higher grades of weaponry to Kyiv in fear of such an outcome, short of what Ukraine needs to win the war decisively.
Though the Western weaponry supplies have been drip-fed, as if testing Russia’s red lines, Russia’s tactic has not delivered the intended outcome thus far of reducing such continued and increasing armament of Ukraine.
"Russia's leadership is worrying a lot about the fact that its nuclear threats do not work. That is why they try to solve the problem of making the threats work again," Pavel Luzin, Senior Fellow at the Center for European Policy Analysis (CEPA), told the Kyiv Independent.
What is Russia's nuclear doctrine?
As one of the eight countries in the world that has publicly announced possession of nuclear weapons, Russia also has a set of rules that dictate when they can be used.
Russian President Vladimir Putin approved a nuclear doctrine in 2020, the provisions of which listed for the first time the threats against which nuclear weapons could be deployed.
It states among other things, that Russia reserves the right to use nuclear weapons if nuclear or other weapons of mass destruction are used against it or its allies.
Russian forces can also deploy their nuclear arsenal in response to any conventional weapons if Russia's existence is threatened. The country's president decides on the use of nuclear arms, it adds.
However, in late February 2024, journalists from the Financial Times (FT) were able to obtain access to secret Russian documents related to Russia's tactical nuclear weapons.
The threshold for the use of these weapons by Russia is much lower than Russian officials have publicly claimed, the FT said.
According to the media outlet, the Russian military could also use them to "deter states from aggression" or "escalating military conflicts."
How many nuclear weapons does Russia have?
According to a March report from the Federation of American Scientists (FAS), Russia currently has a total inventory of 5,580 nuclear warheads (including around 1,200 awaiting dismantlement), the most of any country in the world.
Putin and other Russian officials have reiterated several times since the beginning of the full-scale invasion of Ukraine that Russia is "prepared" for a nuclear war, and could use its nuclear arsenal if necessary.
In February, Deputy Chairman of Russia's Security Council Dmitry Medvedev, said the world risked a global "apocalypse" if Western nations continued to send arms to Ukraine.
And in May, he made similar threats amid discussions about the possible deployment of Western troops to Ukraine, which French President Emmanuel Macron widely supported.
"Sending their (Western) troops to Ukraine will entail a direct entry of their countries into the war, which we must respond to. And, unfortunately, not on the territory of Ukraine," he said.
The threats have also been accompanied by the reported deployment of tactical nuclear weapons to Belarus, as well as joint nuclear exercises between the two countries.
Russia's new nuclear doctrine
As well as Peskov's recent comments, Deputy Foreign Minister Sergei Ryabkov said on Sep. 1 that Russia will change its nuclear doctrine based on an analysis of recent conflicts and the West's "escalation course."
Work on the doctrine changes is at "an advanced stage," according to Ryabkov, but the Russian official did not reveal any deadlines for the document's drafting or the changes to be introduced.
Experts suggest any announcements of a change in doctrine are more for political and psychological effect, rather than a step towards their actual use.
"In this way, it does not matter what will be changed because any changes will have political and psychological senses, but not a military sense itself," Luzin said.
Jacob Kaarsbo, a senior analyst at the Think Tank Europa, echoed Luzin's stance, saying that the Russian government has become more vocal amid talks of allowing Ukraine to use Western long-range weapons to strike Russia back and Ukraine's incursion into Kursk Oblast.
"By making this announcement now, Ryabkov is trying to deter outgoing U.S. President [Joe] Biden and his administration to keep them away from making this decision [to allow Ukraine to strike with Western weapons deep inside Russia]," Kaarsbo told the Kyiv Independent.
Kaarsbo noted that this is the same phenomenon that had previously been observed during the war when Kremlin representatives became more active during discussions of important decisions to support Ukraine.
"That's an old trick from the intelligence book," Kaarsbo said, adding that Russia's nuclear posture has not changed recently, and its latest statements are purely political.
The Kremlin's latest announcement of changes to its nuclear doctrine has not gone unnoticed by its allies as well.
China, which is one of Russia's key partners in helping it stay afloat under Western sanctions, said the day after Ryabkov's announcement that "a nuclear war cannot be won."
The influence of allies is also a deterrent for Russia because the use of nuclear tactical weapons, particularly against Ukraine, would harm Putin himself in the first place, Kaarsbo added.
Yet, Luzin said that the only correct way to deal with Russia is a presumption that if Russia is politically, technically, and organizationally capable of using nuclear weapons, it will use them sooner or later. The world must be ready for the worst-case scenario and make military preparations for this, he added.
"If Russia's leadership realizes that in case of any scale of such use [of nuclear weapons], it will be inevitably eliminated together with all their families, including grandchildren, and that Russia will be totally destroyed and disarmed, that will be an effective deterrence."
"Russia's leadership should be aware that this response will be unacceptably painful for them. And that's the problem because it seems that guys in the Kremlin believe they can survive," Luzin said.