Russia Threatens NATO With Nuclear Weapons if Kaliningrad Is Isolated

Russia has warned NATO that it could use nuclear weapons if the Alliance attempts to isolate the Kaliningrad region.

The warning was contained in a diplomatic document delivered by Russia to NATO and reviewed by Reuters.

In the document, Moscow accused the Alliance of pursuing a “dangerous and reckless course” that, according to Moscow, creates a high risk of direct armed conflict.

Russia claimed that if NATO attempts to isolate the Kaliningrad region, it is ready to use its entire arsenal, “including nuclear weapons.”

The document also mentions Russian strikes on “decision-making centers” in NATO member states at the initial stage of a potential conflict.

The document has not been made public. Reuters reported its contents based on a copy of the diplomatic note reviewed by its journalists.

Statements by Russian Embassies

On September 28, the Russian Embassy in Belgium said that NATO activity near Russia’s borders was increasing. It accused the Alliance of modeling scenarios for isolating the Kaliningrad region and said such actions increased the risk of direct confrontation. The embassy also said Russia was ready to use its “entire arsenal.”

The embassy said this position had been conveyed to NATO headquarters and Belgium’s Ministry of Foreign Affairs.

The following day, Russian diplomatic missions in the United Kingdom and Ireland directly mentioned nuclear weapons.

NATO Response

NATO confirmed that it had received the document and said it had provided a written response. The Alliance emphasized that it is defensive and that its exercises and activities do not pose a threat to Russia.

NATO called on Moscow to end its full-scale invasion of Ukraine, refrain from risky actions toward NATO member states and stop its “irresponsible nuclear rhetoric.”

An unnamed NATO diplomat shared with Reuters that the Russian letter was another attempt by Russia to intimidate Europeans and that NATO’s response was resolute and responsible. The diplomat added that the response again confirmed NATO would not be deterred from supporting Ukraine.

Moscow has linked the statements to increased NATO activity in the Baltic Sea.

The Russian Embassy in Belgium mentioned the Baltic Sentry operation, which NATO launched in January 2025 after damage to critical underwater infrastructure in the Baltic Sea.