This could be a red line for Russia if it goes ahead since it would block Russia's naval base in Crimea from accessing the Mediterranean sea. Turkey is a NATO member and has the benefit of their military tech.
https://www.zerohedge.com/geopoliti...s-without-preconditions-russia-belarus-border
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On Sunday, for the first time, Turkey signaled it is ready to block Russian naval access to the Black Sea."
"Turkey’s foreign minister said Sunday that the situation in Ukraine had become a war, a legal distinction that paves the way for Ankara to potentially ban Russian warships from entering the Black Sea through a strategic chokepoint," The Wall Street Journal reports.
"The terms of the 1936 Montreux Convention is now expected to be triggered. Speaking to CNN Turk Foreign Minister Mevlüt Çavuşoğlu said: “We came to the conclusion that the situation in Ukraine has transformed into a war,” and this means “We will implement all articles of Montreux transparently.”