MOSCOW, May 31. /TASS/. Deputy Chairman of Russia’s Security Council Dmitry Medvedev says Western countries may be making a "fatal mistake" in assuming that Russia will never use tactical nuclear weapons (TNW).

"Just a few years ago, they [the West, NATO countries] were saying that Russia would not engage in an open military conflict with the Bandera regime in order not to quarrel with the West. They miscalculated. There is a war underway," Medvedev wrote on his Telegram channel.

According to him, "they may also be miscalculating with the [possible] use of TNWs."

"However, this would be a fatal mistake. After all, as the Russian president justly pointed out, European countries have a very high population density. And for those enemy countries whose lands are beyond the TNW coverage zone, there is strategic potential," he added.

"No matter how much NATO’s retired old farts babble that Russia will never use non-strategic nuclear weapons against former Ukraine and what’s more, against individual NATO countries, reality is much harsher than their frivolous musings," Medvedev noted.

Medvedev believes it is possible that the conflict between Russia and the West has already entered its final stage.

"Unfortunately, this is neither intimidation nor a nuclear bluff. The current military conflict with the West is developing according to the worst-case scenario," he said.

According to him, there is a constant escalation around the use of NATO weapons.

"Therefore, today no one can exclude the possibility of the conflict shifting to its final stage," Medvedev added.

In an interview with the Economist earlier in the month, NATO Secretary General Jens Stoltenberg suggested NATO allies should reconsider whether Ukraine could use Western-supplied weapons to carry out strikes on military facilities inside Russia's internationally recognized borders. However, Stoltenberg said at a session of the NATO Parliamentary Assembly that there should be no NATO troops on the ground in Ukraine because otherwise, it would be difficult to keep the bloc out of the conflict.

Meanwhile, The New York Times reported, citing its sources, that after his recent visit to Kiev US Secretary of State Antony Blinken said that he planned to suggest that President Joe Biden lift the ban on using American weapons against targets in Russia.

On May 28, Russian President Vladimir Putin said that when speaking about strikes inside Russia, representatives of NATO countries, "should be aware of what they are playing with." According to Putin, Russia is closely monitoring such a discussion. Once Ukraine’s military uses long-range weapons, Moscow will once again have to decide on "a sanitary zone," Putin said.