Washington( CNN) The US has begun stimulating the necessary preparations to sail a warship into the Black Sea, a move that comes amid heightened tensions in individual regions following Russia's seizure of Ukrainian ships and detention of Ukrainian sailors.

For its part, the Russian Ministry of Defense announced Wednesday that its troops in eastern Crimea, which Moscow seized from Ukraine in 2014, conducted a military drill with its Pantsir anti-aircraft missile systems.

Active preparations

Ukraine advises NATO to send more ships to port