Alarm bells have been ringing across Europe over a buildup of Russian troops along the border with Ukraine in recent months. The fear is that Russian President Vladimir Putin is contemplating a rerun of 2014, when Russian forces annexed the Crimean peninsula and provided support for a separatist, pro-Russian insurgency in the Donbas region of eastern Ukraine. Moscow denies having any plans to invade, but U.S. officials have said such a move is possible. President Biden is due to talk with Mr. Putin about the rising tensions in a video call Tuesday, in which he is expected to warn off the Russian leader from any invasion.
So far it is unclear whether Russia wants to reassert control of the former Soviet republic, or to warn off the U.S. and NATO from developing closer ties with Ukraine and maintain it as a buffer between Moscow and the West.