The U.S. Navy’s dock landing ship Fort McHenry pulled into the Romanian port of Constanta on Monday for what officials term a “routine port visit” after transiting the Dardanelles Strait from the Mediterranean Sea the day before.

That makes Fort McHenry the first American warship to enter the Eastern European waterway since Russia seized three Ukrainian vessels on Nov. 25 in the Kerch Strait.

“We routinely operate in the Black Sea consistent with international law and the Montreux Convention and will continue to do so,” said Navy 6th Fleet spokesman Cmdr. Kyle Raines.

The Sea of Azov won’t become the new South China Sea (and Russia knows it) Whereas China’s claims of maritime rights over most of the South China Sea have been rejected by an international tribunal, Russia’s rights in the Kerch Strait are well-defined.

Homeported in Mayport, Florida, the Whidbey Island-class warship Fort McHenry is embarking the 22nd Marine Expeditionary Unit from Camp Lejeune, North Carolina.

They’re part of the Kearsarge Amphibious Ready Group., which also includes the Wasp-class amphibious assault ship Kearsarge, the San Antonio-class amphbious transport dock Arlington and their embarked units.

Asked if the other ships would join the Fort McHenry in the Black Sea, Raines said only that they’re “underway in the Mediterranean conducting maritime security operations.”

“USS Fort McHenry’s transit into the Black Sea reaffirms our collective resolve to Black Sea security and enhances our strong relationships with our NATO allies and partners in the region,” said Vice Adm. Lisa M. Franchetti, commander of the U.S. 6th Fleet, in a separate release.

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Franchetti’s vocal support for NATO’s collective resolve in the region comes amid tensions generated by Russia’s ongoing efforts to destabilize Ukraine.

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Russia seized the Crimea Peninsula from Ukraine, a non-NATO state, in 2014, triggering economic sanctions by the U.S. and European Union and retaliatory efforts by Moscow to sway America’s 2016 presidential election.

Moscow continues to support armed separatists waging war against Kiev for control of a large southeastern chunk of Ukraine known as Donbass.

Russian forces in late November fired on and seized the three Ukrainian vessels sailing through the narrow Kerch Strait to reach the eastern Ukrainian port of Mariupol in the Sea of Azov, which borders Donbass.

Moscow continues to detain the 24 sailors and vows to put them on trial.

That’s sparked calls in Washington to arm Ukraine with Harpoon anti-ship missiles and heap more sanctions on Russia, but no decisions have been reached on Capitol Hill or the White House.

The amphibious warship Fort McHenry sailed through the Mediterranean Sea's Strait of Messina on Jan. 3. (U.S. Navy photo by Mass Communication Specialist 3rd Class Chris Roys/Released)

The last U.S. warship to operate in the Black Sea was the Spain-based guided-missile destroyer Carney.

The Arleigh Burke-class vessel spent much of August in the area before departing the Black Sea on Aug. 27. It was Carney’s third visit there in 2018.

Two other guided-missile destroyers — the Ross and the Porter — also sailed into the sea last year.

The Military Sealift-operated expeditionary fast transport ship Carson City visited Constanta in August to drop off soldiers from the U.S. Army’s Bravo Company, 2nd Battalion, 5th Cavalry Regiment and shuttle troops and equipment from the Romanian port to Poti, Georgia.

The 6th Fleet’s Italy-based command and control flagship Mount Whitney entered the Black Sea on July 7 to participate in the Sea Breeze 2018 exercise, four months after the dock landing ship Oak Hill and the 26th MEU arrived for the Romanian-led Spring Storm 2018 maneuvers.