Ukraine plans to send navy ships through the Kerch Strait, an official said in an advance notice to Russia on Friday.
That’s the same location where Russia’s military opened fire and seized three Ukrainian naval vessels last month, further escalating tensions between the two countries.
In revealing Ukraine’s plans, Defense Minister Stepan Poltorak told reporters that the movement had to occur “otherwise Russia will fully occupy the Sea of Azov."
Ukraine occupies sea ports on the Black Sea and on the Sea of Azov. The bodies of water are connected via the Kerch Strait, which separates Crimea from Russia.
In the incident that occurred on Nov. 25, Russian coast guard crews boarded two naval artillery boats, as well as a tugboat, and apprehended the vessels, Ukraine’s navy said at the time.
The following day, Ukrainian President Petro Poroshenko deemed it “an act of aggression,” and called it “a very serious threat.” He also insisted on the sailors and ships’ release and signed a decree to introduce martial law across the country for 30 days.
Reacting to the situation, United Nations Ambassador Nikki Haley said Russia’s actions were an “outrageous violation of sovereign Ukrainian territory” and marked “yet another reckless Russian escalation.”
"[It's] an arrogant act that the international community must condemn," she added. "The United States will continue to stand with the people of Ukraine."
Russian Foreign Minister Sergey Lavrov, while making remarks in Rome, dismissed the notion that his country could release or exchange the captured Ukrainian seamen. It was premature to speak about any offers of a prisoner swap until Russia's investigation of the incident is completed and the servicemen are put on trial for violating the Russian border, Lavrov reportedly said.
Fox News’ Samuel Chamberlain, Lucia I. Suarez Sang and The Associated Press contributed to this report.