Vice President Kamala Harris and Romanian President Klaus Iohannis on Friday met amid growing concerns about the influx of displaced people fleeing Ukraine for Romania and elsewhere in eastern Europe because of Russia’s military operation. The Ukrainian refugee crisis is a problem that Biden administration officials and European leaders warn will likely get more complicated in the days and weeks ahead.

Harris’ talks in Bucharest with Iohannis came after she spent yesterday in Poland, which has already welcomed some 1.5 million Ukrainians since the invasion began last month. She met in Warsaw with Polish President Andrzej Duda and Prime Minister Mateusz Morawiecki, Ukrainian refugees and others in hopes of getting a fuller picture of the unfolding humanitarian crisis.

Harris told Iohannis soon after arriving in Bucharest that she sought to reaffirm commitment to this partnership and also to the NATO alliance as a whole.

The southeastern European country of Romania, a nation of about 19 million residents, had taken in more than 84,000 displaced people as of Tuesday, according to United Nations data. Other countries on NATO’s eastern flank, including Hungary, Moldova and Slovakia, have also welcomed tens of thousands of refugees.