Crimea annexation, Moscow's penetration into the Mediterranean and Ankara's 'red lines'
Russia's annexation and militarisation of Ukraine's Crimean Peninsula represents a serious threat to security in the Black Sea and Eastern Mediterranean regions.
Chief among the countries affected is Turkey. Ties between Ankara and Moscow were once cordial but soured dramatically after Turkey shot down a Russian fighter jet near the Syrian border in November 2015.
Tensions have been further inflamed by Russia's military intervention in Syria.
Given the precarious geopolitical backdrop, is there a way for Ankara and Moscow to rekindle their warm relations of the past?
Or will the situation get worse, before it gets better? Answers to those questions come from our guest in the Viewpoint studio, Istanbul University Professor Dr. Kivanç Ulusoy.