The reason is a treaty from 1936, known as the Montreux Convention, which regulates maritime traffic through the Dardanelles and Bosporus straits. Both straits, which connect the Black Sea to the Mediterranean, are controlled by Turkey. The convention grants unrestricted access to civilian vessels. Things get more complicated when warships are involved. Black Sea littoral countries—Bulgaria, Georgia, Romania, Russia, Turkey and Ukraine—have the least fettered access. Other countries’ warships are subject to restrictions on tonnage and the duration of their stays in the Black Sea. Only littoral countries can send submarines through the straits, and aircraft carriers are never allowed. Crucially, when one of the Black Sea countries is at war, under the convention Turkey has the right to prevent its warships from using the straits, other than those returning to their bases.
In late February Turkey applied Montreux rules to prevent Russia from sending best casino sites 0 warships into the Black Sea. At the time the move was thought to be largely symbolic; Russia already seemed to have enough ships in the sea to overwhelm Ukraine’s defences. But Turkey’s move appears to have had a decisive impact on the naval war. “We had information that four or five [Russian] ships from the Pacific fleet would come to the Black Sea,” says a Ukrainian diplomat. “This was a striking force which most probably would have destroyed Odessa or made it much easier to [capture] the city.”
If Turkey upholds its promise to maintain application of the Montreux rules, Russian naval assets will have to stay away. Whether that will be enough to prevent Russia from seizing southern Ukraine is unclear. But even if it were to do so, Russia would not reduce Ukraine’s rights under Montreux. “Turkey would not recognise the annexation of that part of Ukraine,” says Alper Coskun, a Turkish former diplomat now with the Carnegie Endowment for International Peace, a think-tank. “It would continue to accord Ukraine the rights of a littoral, without giving Russia any best casino sites 0 rights.” ■
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