entered kharkiv, this country's second largest city. u.s. officials say most of the russian forces amassed around ukraine are now fighting inside the country. in response, nato allies are doubling down on measures intended to punish russia. focusing in part on the country's financial institutions. and a symbol of the resistance here in the u.s.. governors of texas, utah and ohio have banned retailers from selling russian products, specifically vodka. liquor stores in new hampshire, kansas and michigan, you see here, also taking russian vodka off their shelves. and instead, provoking ukrainian spirits. overseas, germany is preparing to close its airspace to russian planes. joining the united kingdom, romania and the baltic states, have all also taken that steps. it comes as un officials say more than 150,000 ukrainian refugees have already flooded that country. nbc's ellison barber joins us at a checkpoint where thousands