WASHINGTON—The Pentagon said Thursday that it carried out a rare flight over Ukraine under the international Open Skies Treaty to “reaffirm U.S. commitment to Ukraine” amid heightened Russia-Ukraine tensions.
It was the second such U.S. military gesture in two days after Russia last month shot at and seized three Ukrainian naval vessels and their crew members off Crimea. The U.S. Navy on Wednesday sent a warship through the Sea of Japan in a rare challenge to Russia’s maritime claims in international waters.
“Russia’s unprovoked attack on Ukrainian naval vessels in the Black Sea near the Kerch Strait is a dangerous escalation in a pattern of increasingly provocative and threatening activity,” the Pentagon said in a statement. “The United States seeks a better relationship with Russia, but this cannot happen while its unlawful and destabilizing actions continue in Ukraine and elsewhere.”
Russia has claimed the ships trespassed into Russian territorial waters.
The Open Skies Treaty gives 34 signatory states the right to gather information about the military forces and activities of one another. Pentagon considered Thursday’s flight “extraordinary” because it was carried out bilaterally—rather than through treaty negotiations—at the request of the arms control directorate of the General Staff of Ukraine’s armed forces.
U.S. officials wouldn’t specify the Thursday plane’s flight path but said it was near Crimea, the Ukrainian region seized by Russia in a 2014 invasion. They used a U.S. Air Force OC-135 observation plane, which was specifically designed for such missions, with U.S., Canadian, German, French, UK, Romanian and Ukrainian observers aboard, the Pentagon said.
The last time the U.S. military conducted a similar flight was in 2014, after Russia’s military invasion of Crimea, U.S. defense officials said.
The U.S. Navy conducts such operations around the world on a routine basis, putting a particular focus on such patrols to challenge China’s maritime claims in the South China Sea. Wednesday’s patrol was the first operation targeting Russia in this region since 1987, an official said.
U.S. military officials also were planning to send a warship into the Black Sea, in a third challenge to Russian claims, said a U.S. military official.
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