The wife of President Joe Biden was due to meet U.S. service members and embassy personnel, displaced Ukrainian parents and children, humanitarian aid workers and teachers during the four-day trip, her office said.

Biden, who teaches English and writing at a community college in Virginia, will also meet Romania’s first lady, Carmen Iohannis, an English teacher, as well as the president of Slovakia Zuzana Caputova.

On Sunday, celebrated as Mother's Day in the United States, Biden will meet Ukrainian mothers and children who have been forced to flee their homes because of Russia's war against Ukraine, her office said.

U.S. presidential wives have little policy-making power, but often serve a "soft power" role, taking an administration's message to voters and abroad.

U.S. Secretary of State Antony Blinken, Defense Secretary Lloyd Austin and Speaker of the House Nancy Pelosi have all paid visits to Ukrainian President Volodymyr Zelenskiy in Kyiv. President Biden visited Poland in March.

More than 840,000 Ukrainians have fled to Romania, and around 80,000 remain. State television will air weekly language lessons for children from Friday, although only 2,000 Ukrainian children are enrolled in Romanian schools.

Just over 380,000 Ukrainians have entered Slovakia since the beginning of the war, but most journeyed further to other European countries. The country has been a strong supporter of Ukraine, shipping aid and weapons including its sole battery of the Soviet-era S-300 air defense system.

Among those accompanying Biden are Assistant Secretary of State for European and Eurasian Affairs Karen Donfried, Senior Director for Multilateral Affairs at the National Security Council Curtis Ried, and Director for Humanitarian Affairs at the National Security Council Daniel Dieckhaus.