According to diplomatic sources, Turkey has threatened Russia with a blockade of the Bosphorus Strait.

The threat to close the Bosphorus to Russia comes from a report by Hvylya, citing a Turkish diplomatic source. According to the source, Turkish Prime Minister Tayyip Erdogan yesterday spoke with Russian President Vladimir Putin on the phone and warned of the consequences for conflict with Ukraine. The Hvylya source was also reported on by UNIAN.

Concerns were also raised about the possible threat to ethnic Crimean Tatars in the region, citing recent murders and communications with Tatar leadership. Erdogan’s call to Putin warned that if Russia invades Ukraine, and so-called ‘Crimean self-defense’ forces engage in violence against the Tatar minority, Turkey will be forced to close passage into the Black Sea to Russian ships.

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While the sea-port of Sevastopol has been lauded for its strategic importance as the only warm water port in the Black Sea Russia controls, restriction to it would be a self-made prison. Russian activity in the eastern basin of the Mediterranean is dependent on this passage to Crimea, and restriction would cut off arms shipments between Russia and the Syrian port in Tartus, as as well as lucrative arms deals with Egypt. As Amatzia Baram of Haaretz writes, “for Russian President Vladimir Putin, the Sevastopol port is indirectly the key to Syria and perhaps to Egypt and the entire Mediterranean in the future.”

http://ukrainianpolicy.com/turkey-warns-russia-it-will-blockade-bosphorus/