A Russian military unit will be testing the Iskander ballistic missile near the Black Sea peninsula of Crimea this month, the press service of the southern region of Krasnodar said Monday. The tests, which are in range of many Eastern European countries -- not to mention Ukraine -- further ratchet up the tension that has been escalating between U.S.-led NATO and Russia since Moscow annexed Crimea 16 months ago and got involved in the eastern Ukraine conflict.

"Servicemen of a missile unit of the Southern Military District deployed in the Krasnodar Territory began preparations for drills and live-firing of tactical Iskander-M missile systems that will start in late July at the Kapustin Yar range in the Astrakhan Region," reports Tass, a Kremlin-run Russian news site. Krasnodar and Astrakhan are in southern Russia, east of the Black Sea and Crimea. 

Russia's recent testing of the missile system, which can carry nuclear weapons, has been part of tit-for-tat threats between Moscow and Washington that both sides would place nuclear weapons back in European territory, namely in the Russian exclave of Kaliningrad on the Baltic Sea and in the U.K. If either side did make such a move, it would be in breach of Cold War treaties signed during the fall of the Soviet Union in 1991. 

During discussions on the possibility that the U.S. could place nukes back in the U.K., British Foreign Secretary Phillip Hammond said Western forces have “to send a clear signal to Russia that we will not allow them to transgress our red line” and that “a decision that we would make together, if that proposition was on the table.”

Earlier this month, Russia began talks to provide its small ally Armenia with a version of the missile, hoping to draw on old Soviet allegiances that have also seen an increased Russian military presence in many former Soviet republics.