First lady Jill Biden makes unannounced visit to Ukraine war zone, holds surprise Mother's Day meeting with Zelenskyy's wife

• Jill Biden unexpectedly crossed into Ukraine on Sunday.
• She held a Mother's Day meeting with Ukraine's first lady.

First Lady Jill Biden made an unexpected visit into Ukraine on Sunday, several outlets reported.

Biden's visit to an active war zone was a rare visit from a spouse of a sitting US president, The Washington Post reported.

The Associated Press reported that Biden crossed over into the western Ukrainian town of Uzhhorod from Slovakia. She held a surprise Mother's Day meeting with Olena Zelenskyy, Ukrainian President Volodymyr Zelenskyy's wife.

"I wanted to come on Mother's Day," Biden told Zelenskyy. "I thought it was important to show the Ukrainian people that this war has to stop and this war has been brutal and that the people of the United States stand with the people of Ukraine."

The Washington Post reported that Zelenskky thanked Biden for her courage in coming into a war zone. Biden is the highest profile US official to enter Ukraine since the start of Russia's invasion.

"We understand what it takes for the U.S. first lady to come here during a war when military actions are taking place every day, where the air sirens are happening every day -- even today," Zelenskyy told Biden.

Biden has been on a trip to eastern Europe since Friday. Her visit in Ukraine comes ahead of Russia's 'Victory Day' on May 9, an annual event celebrating the Soviet Union defeating Nazi Germany in 1945 during World War II.

It's anticipated that Russian President Vladimir Putin will announce some sort of victory in Ukraine on Monday, and the Post reported that there's growing concern the attacks on Ukraine will increase, especially in eastern Ukraine.

The AP reported that Biden's trip is limited to western Ukraine.

Biden and Zelenskyy met at a school that was turned into a transitional home for Ukrainians fleeing the war in other parts of the country. The pair met with a group of kids who were making bears from tissue-paper to give as gifts for Mother's Day, the AP reported.