The US first lady met her Ukrainian counterpart Olena Zelenska at a school sheltering civilians, including children displaced by the conflict, near Ukraine’s border with Slovakia.
“I wanted to come on Mother’s Day,” Biden told reporters.
“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.”
Separately, Canadian leader Trudeau visited Irpin, a suburb on the northwest edge of Kyiv that was the scene of heavy fighting in the early weeks of the conflict.
Local mayor Oleksandr Markushyn, posted pictures on social media and said Trudeau “came to Irpin to see with his own eyes all the horror that the Russian occupiers had done to our city.”
While on the ground, the key battles were being fought in Ukraine’s east.
Civilians have now been evacuated from Mariupol’s Azovstal steelworks, leaving a small force of defenders holed up in its sprawling network of underground tunnels and bunkers.