The United Nations estimates 6.5 million people have been displaced by the war, coupled with more than 3 million who have fled Ukraine.
As Russian forces target the outskirts of the western city of Lviv, Zelenskyy is accusing Russia of creating a humanitarian catastrophe by blocking critical supplies to his country's largest cities.
Overnight, the Ukrainian president appealed directly to Moscow, Chris Livesay reports for"CBS Saturday Morning." But the heartache tells the truth. In Kyiv, Ukraine's capital, a son cried over the body of his mother, who was killed by falling debris. And Mariupol — the scene of Russia's most vicious onslaught — is encircled in siege warfare, leaving hundreds of thousands of civilians trapped without food, water, heat and electricity.