During the recent Russian troop buildup in occupied Crimea and across Ukraine’s eastern borders, Moscow announced that it was closing off parts of the Black Sea and Kerch Strait to foreign warships and other vessels from April 24 to October 31. The closure comes at a time of heightened political and military tensions not seen since the annexation of Crimea in 2014 and represents yet another unprovoked escalation in Moscow’s ongoing campaign to undermine and destabilize neighboring Ukraine.
The Kerch Strait is crucial to Ukraine as it connects the Sea of Azov to the Black Sea and hence ensures free passage to Ukrainian vessels from its port cities such as Mariupol to the outside world.
Russia is all too aware of the importance of the Black Sea.
Over the past two decades, Russia has consolidated its presence there by annexing Georgia’s Abkhazia region in 2008 and Ukraine’s Crimea in 2014. The Black Sea Fleet is responsible for bringing supplies to Russian forces in Syria, mostly based in the port of Tartus and Khmeimim air base, as well as for patrolling the eastern Mediterranean. The Kremlin’s 2015 Maritime Doctrine clearly prioritizes the Black Sea as a pillar of its power projection.
Once almost equally divided between littoral states, the annexation of Crimea tipped the balance of military power in the Black Sea in favor of Russia. Not only did Moscow cancel existing agreements with Ukraine which limited its Black Sea Fleet in Sevastopol, but it stationed new military ships and submarines and installed a dense network of advanced weapons systems such as the S-400, the S-300, Pantsir-S1, and the Bastion-P anti-ship systems across the peninsula. It has also significantly increased its Exclusive Economic Zone and its Black Sea coastline.