Russian President Vladimir Putin's latest nuclear move has broken a pact signed with his Chinese counterpart Xi Jinping, just days after agreeing to it.
The President of China Xi Jinping visited Russia last month and the two leaders agreed they would not deploy nuclear weapons beyond their own sovereign territory.
"All nuclear powers must not deploy their nuclear weapons beyond their national territories and must withdraw all nuclear weapons deployed abroad," a joint communique said.
But just days after the agreement was announced, Russia said it would be placing its tactical nuclear weapons near Belarus' borders with NATO countries.
The weapons "will be moved to the western border of our union state and will increase the possibilities to ensure security," Russian ambassador to Belarus Boris Gryzlov told Belarusian state television.
"This will be done despite the noise in Europe and the United States."
Russia Defence Minister Sergei Shoigu added Moscow is defending the "security of our allied state".
"Some of the Belarusian attack aircraft have acquired the ability to strike enemy targets with nuclear weapons," Shoigu said.
Three NATO countries share a border with Belarus. The northern border is shared with Lithuania and Latvia while the western border is shared with Poland.
This is all a part of NATO's eastern flank which has been bolstered with additional troops and military equipment following Russia's invasion of Ukraine.
This is the first time Moscow has moved nuclear weapons outside of Russia's borders since the fall of the Soviet Union.
The former US ambassador to Russia Michael McFaul believes the move by Putin and the President of Belarus Alexander Lukashenko has "humiliated" Xi.
"Remember, Luka was just treated to a fancy state visit to China. Xi just came to Moscow. Can't imagine this decision is going down well in Beijing," McFaul said.
It's the latest in a series of escalating nuclear threats since Putin launched Russia's invasion of Ukraine in February last year.
An analyst at the UK research institute Chatham House believes Russia will continue with their barrage of threats.
"Fears of escalation to the point at which Russia may resort to nuclear use have constrained the willingness of Western governments to provide war-winning military support to Ukraine, and have shown Russia that nuclear threats - no matter how implausible - work," Keir Giles said.
