Former Russian President Dmitry Medvedev is warning Thursday that the "pumping of Ukraine by NATO countries with weapons" brings the risk of the conflict "turning into a full-fledged nuclear war." 

Medvedev, who now is the deputy chairman of Russia’s Security Council, wrote in a Telegram post that such an escalation would be a "catastrophic scenario for everyone." 

"The pumping of Ukraine by NATO countries with weapons, the training of its troops to use Western equipment, the dispatch of mercenaries and the conduct of exercises by the countries of the Alliance near our borders increase the likelihood of a direct and open conflict between NATO and Russia instead of their ‘war by proxy,’" he said. 

Russian Security Council Deputy Chairman and the head of the United Russia party Dmitry Medvedev chairs a meeting on saving businesses and jobs in foreign companies via video link at Gorki state residence, outside Moscow, Russia, on March 16.

Russian Security Council Deputy Chairman and the head of the United Russia party Dmitry Medvedev chairs a meeting on saving businesses and jobs in foreign companies via video link at Gorki state residence, outside Moscow, Russia, on March 16.

KREMLIN CALLS FINLAND’S NATO MOVE A THREAT TO RUSSIA 

"Such a conflict always has the risk of turning into a full-fledged nuclear war," Medvedev added. 

"You just need to think about the possible consequences of your actions," he also wrote in the post. 

Russian President Vladimir Putin looks on during the Victory Day military parade marking the 77th anniversary of the end of World War II in Moscow, Russia, on Monday, May 9.

Russian President Vladimir Putin looks on during the Victory Day military parade marking the 77th anniversary of the end of World War II in Moscow, Russia, on Monday, May 9. (Mikhail Metzel, Sputnik, Kremlin Pool Photo via AP)

The message comes about a week after Russia’s Foreign Ministry claimed Moscow will not unleash nuclear weapons during the war in Ukraine despite top officials' threatening rhetoric. 

CLICK HERE TO GET THE FOX NEWS APP 

Maksym, 3, is photographed with his brother, Dmytro, 16, on top of a destroyed Russian tank, on the outskirts of Kyiv, Ukraine, on May 8.

Maksym, 3, is photographed with his brother, Dmytro, 16, on top of a destroyed Russian tank, on the outskirts of Kyiv, Ukraine, on May 8. (AP/Emilio Morenatti)

Alexei Zaitsev said last Friday that "we have repeatedly refuted insinuations about Russia’s possible use of nuclear weapons in the course of the special military operation in Ukraine," which has now lasted 78 days. 

"Russia adheres to the principal that there can be no winners in a nuclear war and it must not be unleashed," Zaitsev added, according to a translation from Reuters.