Russia says it hopes nuclear deterrence will "knock some sense" into the West over plans to send fighter jets to Ukraine.
In a briefing today, foreign minister Sergei Lavrov says Russia regards Belgium's pledge to send US-made F-16 warplanes to Kyiv as a "signal action".
He adds, according to the RIA state news agency: "They are trying to tell us that the United States and NATO would stop at nothing in Ukraine.
"Nevertheless, we hope that the Russian-Belarusian drills on the use of non-strategic nuclear weapons that are under way now will knock some sense into our opponents by reminding them about the catastrophic consequences of further nuclear escalation."
Russia has been carrying out nuclear exercises throughout May, and are currently conducting joint air force and air defence ministry drills with Belarus.
For context: Earlier this week, Belgium agreed to send Ukraine 30 F-16 fighter jets by 2028.
It marked part of a security pact Volodymyr Zelenskyy and Alexander De Croo, the Belgian prime minister, signed in Brussels on Tuesday.
As part of the agreement, Belgium will also provide Ukraine with at least €977m (£832m) in military aid.
After securing more NATO support, Mr Zelenskyy again demanded the West lift restrictions on the use of supplied weaponry to hit targets in Russia, saying it was "unfair" that Ukraine could not strike back.