Biden condemns ‘invasion’ of Ukraine; US and allies impose sanctions on Russia

A man holds a poster in support of Ukraine as he attends a demonstration near the Russian embassy to protest against the escalation of the tension between Russia and Ukraine in Berlin, Germany, Tuesday. (AP Photo/Markus Schreiber)

U.S. President Joe Biden delivers remarks on developments in Ukraine and Russia, and announces sanctions against Russia, from the East Room of the White House Tuesday in Washington, D.C. The White House earlier in the day called Russia's deployment of troops into two pro-Russian separatist regions of Ukraine the beginnings of an invasion. (Drew Angerer/Getty Images/TNS)

WASHINGTON — The United States and its allies on Tuesday swiftly imposed economic sanctions on Russia for what President Joe Biden denounced as the beginning of an “invasion of Ukraine,” unveiling a set of coordinated punishments as Western officials confirmed that Russian forces had begun crossing the Ukrainian border.