NATO ships from the Standing NATO Mine Counter-Measures Group 2 (SNMCMG-2) entered the Black Sea, a military-diplomatic source said.
"The flagship SNMCMG-2, missile frigate Avier, minesweeper Rimini (both come from the Italian Navy), Greek corvette Machitis and Turkish minesweeper Akchey traveled through Black Sea straits and entered the Black Sea," the source said.
According to the source, the NATO ships are heading to the Bulgarian port of Burgas, where they plan to participate in joint exercises with the navy of Bulgaria.
The time period, during which warships of non-Black-Sea countries are allowed to stay in the waters of the Black Sea is limited to 21 days, in accordance with the Montreux Convention, adopted in 1936. NATO has repeatedly violated the terms of staying in the Black Sea, to which Russia had to react.