The Institute for the Study of War said in its latest assessment that Russian dictator Vladimir Putin and key Kremlin officials had initially increased their references to the use of nuclear weapons from Putin’s Sept. 30 annexation speech and throughout October, likely to pressure Ukraine into negotiations and to reduce Western support for Kyiv.

However, the Russian Ministry of Foreign Affairs released a statement on Nov. 2 on “the prevention of nuclear war,” stating that Russia “is strictly and consistently guided by the postulate of the inadmissibility of a nuclear war in which there can be no winners, and which must never be unleashed.”

"The Kremlin’s rhetorical shift indicates that senior Russian military commanders and elements of the Kremlin are likely to some extent aware of the massive costs for little operational gain Russia would incur for the use of nuclear weapons against Ukraine or NATO," the ISW found.