MOSCOW, May 31. /TASS/. The Russian Black Sea Fleet’s patrol ship Smetlivy has left Sevastopol and is currently en route to the coast of Bulgaria in order to monitor NATO drills, a source in the region’s security forces informed TASS.

"Last night, the patrol ship has left Sevastopol. Smetlivy has embarked on this trip in order to monitor the NATO air defense drills set to be held on the territory of Bulgaria and near the Bulgarian coast," the source stated.

A series of multinational and national drills (Saber Guardian - 2019, Strike Back - 2019, Shabla - 2019 and Swift Response - 2019) will be held in May-June 2019 on the territory of Bulgaria, Romania, Hungary, Croatia, Slovenia and North Macedonia on the initiative of NATO.

Up to 6,000 military officers from Bulgaria, the US, the UK, Ukraine, Greece, North Macedonia, Canada and Italy are set to participate in the drills. The aim of the exercises is to improve the troops’ operational capabilities and compatibility of various military units.