. "to the east and northeast" . "border" . "Ukraine and Russia" . "border checkpoint" . "Russia-Ukraine border" . "border with Russia" . . "Russo-Ukrainian border" . . "Russia's border with Ukraine" . "an international border" . "Ukrainian border" . "Russian border with Ukraine" . . "Ukrainian\u2013Russian border" . "Ukrainian-Russian border" . "Russian-Ukrainian" . "Russia\u2013Ukraine border" . "Russia\u2013Ukraine" . . "Ukraine-Russia border" . "Russo-Ukrainian" . "the border" . . . . . . . "Ukraine with Russia" . . "Russia\u2013Ukraine border" . . "crossing of border" . "state borders" . . "Russia" . "border with Ukraine" . . . . . . "Russian border" . . . "Russian-Ukrainian border" . "border of Ukraine with Russia" . "Ukraine border" . "Russia-Ukraine Border" . "1991" .