NATO has formally condemned what it calls Russia's "irresponsible nuclear rhetoric" after Moscow sent the alliance a written warning that it would be ready to use nuclear weapons if the West attempted to isolate the Russian exclave of Kaliningrad.
The warning, contained in a document classed as a "non-paper" — diplomatic jargon for an informal communication — was sent to NATO and seen by Reuters on Wednesday. In it, Moscow accuses the alliance of a "dangerous and reckless course" around Kaliningrad that carries what Russia describes as high risks of a direct armed conflict erupting between Russia and NATO.
Moscow's warning
The document warns that a confrontation could include "Russian strikes against decision-making centers in the alliance's member states right from the outset of the conflict." Its most alarming line states that "Russia will be ready to use the entire arsenal of forces and capabilities at its disposal, including nuclear weapons, in order to defend its territory should NATO countries undertake any attempt aimed at isolating the Kaliningrad Region from the rest of the country."
The private message was accompanied by public statements from Russian embassies in at least three European countries over the past three days accusing NATO of escalating tensions through military exercises and planning scenarios involving Kaliningrad, according to Reuters. The Russian embassy in Ireland explicitly mentioned nuclear weapons. The statements simultaneously claimed Russia had no intention of attacking NATO countries — a denial that rings hollow coming from a regime that denied any intention to attack Ukraine before launching its full-scale invasion in February 2022.
Kaliningrad is a heavily militarised Russian territory sandwiched between NATO members Poland and Lithuania on the Baltic coast. The Kremlin has long stationed missiles and air assets there as a forward outpost against the West.
NATO's response
NATO pushed back forcefully. Alliance spokesperson Allison Hart said Tuesday that "Russia's use of hybrid tactics is a sign of desperation. But we will not be dissuaded from our support to Ukraine," adding that the alliance has "what it takes to defend every inch of allied territory and remain strong, ready, and able to counter any threat."
"We strongly denounce the threat of force, including any irresponsible nuclear rhetoric," Hart said. "We call on Russia to end its unprovoked war in Ukraine." She stressed that NATO "is a defensive alliance and none of our activities or exercises pose a risk to any part of Russia."
The exchange comes as European governments accuse Moscow of stepping up a "hybrid war" across the continent, including sabotage and arson attacks — charges the Kremlin denies, just as it denies its widely documented sabotage operations. Lithuanian officials rejected the Russian warnings as unfounded psychological pressure, condemned the threats of force, and said they maintain evacuation plans and would resist if attacked.
A familiar playbook
The nuclear sabre-rattling is a well-worn Kremlin tactic. Since 2022, Putin has repeatedly invoked Russia's nuclear arsenal to try to frighten Western capitals into curtailing their support for Ukraine — threats that NATO has consistently treated as coercion rather than credible intent, while quietly adjusting its own deterrence posture. This latest letter, tying the nuclear threat to Kaliningrad, appears designed to manufacture a pretext: conjure a Western threat to Russian territory where none exists, then present the nuclear option as a "defensive" necessity.
The timing is telling. Russia's warnings over Kaliningrad surfaced just as Moscow expanded its attacks on Ukrainian civilian infrastructure and as NATO defence ministers met in Brussels to discuss Russian sabotage operations in Europe. The Kremlin manufactures crises on multiple fronts at once, hoping at least one pressure point gives way.
But the alliance's answer has been unambiguous: the support for Ukraine continues, the defensive posture holds, and nuclear blackmail will not rewrite Europe's borders or its resolve.
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