The encounter, first reported by Russia's RIA news agency, cited the defense ministry as saying the U.S. Navy aircraft, an ЕР-3E Aries II plane, did not violate Russian air space.
In a statement, the State Department said the Russian jet "engaged in an unsafe interaction with a U.S. EP-3 in international airspace, closing to within 5 feet (1.5 meters) and crossing directly in front of the EP-3's flight path."
"This is but the latest example of Russian military activities disregarding international norms and agreements," the statement said, calling on Russia "to cease these unsafe actions."
"After the surveillance plane of the U.S. Navy had changed its course to move away from the border, the Su-27 returned to its base," RIA quoted the Russian defense ministry as saying.
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