KYIV: Ukraine's Defence Minister Oleksii Reznikov called on Thursday for the international community to take tough measures against Russia, including port restrictions on Russian ships, in response to Russian navy drills in the Black Sea.

"Now we expect unified reaction also: when RUS (Russian) ships can't enter world's ports, they'll understand the price of their impudence," Reznikov wrote on Twitter.

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In a related statement, Ukraine's military said navy forces were ready for any development or provocation from Russia. Russia has launched navy exercises in the Black Sea, which Ukraine says has made shipping there virtually impossible.