LONDON (Reuters), – President Vladimir Putin’s most trusted ally warned Thursday the West that an increase in military support to Ukraine from the United States, its allies and other countries could trigger a conflict with NATO.

Former president Dmitry Medvedev, now deputy chairman of Russia’s security council, said such a conflict with NATO always carried the risk of turning into a full blown nuclear war.

Russia invaded Ukraine Feb. 24, killing thousands, destroying vast areas of former Soviet country and raising fears about the worst confrontation between the United States of America and Russia since the 1962 Cuban Missile Crisis.

Medvedev stated in Telegram that NATO countries are pumping weapons into Ukraine and training soldiers to use Western equipment. He also said that mercenaries were being sent in by Alliance countries.

Medvedev stated that such a conflict has the potential to escalate into full-fledged nuclear warfare. This will lead to a disaster for all.

Russia and America are two of the most powerful nuclear countries on the planet. Russia is home to 6,257 nuclear warheads and NATO’s three major nuclear powers, the United States, United Kingdom, and France, have approximately 6,065 warheads each, according the Washington-based Arms Control Association.

Putin claims that the Ukraine “special military operation” is needed because Russia was using Ukraine as a threat to Russia. Moscow also had to protect Russian-speaking citizens from persecution.

Putin claims that Russia and Ukraine are one nation. He sees war as an unavoidable confrontation with the United States.

Ukraine claims it is fighting an empire-style land grab, and Putin’s accusations of genocide seem absurd. Kyiv claims that Putin’s invasion only reinforced the desire of the Ukrainian people to move westwards and get out of Russia.