MOSCOW (AP) — About 3,000 troops from 19 countries are taking part in military drills in the Black Sea, an exercise that has raised concerns in Russia.

The 12-day Sea Breeze 2019 exercise, involving Ukraine, the U.S., a dozen other NATO allies and a few other nations, began Monday in the northwestern part of the Black Sea. It will involve 32 warships and 24 aircraft.

The Russian military says it is monitoring the exercise.

Relations between Russia and the West have plummeted to post-Cold War lows in the wake of Moscow's 2014 annexation of Ukraine's Crimean Peninsula and support for pro-Russian insurgents in eastern Ukraine.

Moscow has voiced concern about previous NATO's drills near its borders, saying they threaten its security, while NATO allies have expressed worries about Russian military maneuvers.