Fighting has intensified around Ukraine's capital, while Russian forces bombard cities across the country, killing civilians who are unable to escape.
Invading Russian troops have redeployed off the main road north of Kyiv, moving into towns and forests as Ukrainian defenders have thwarted their attempts to move south with air and ground attacks.
Ukraine's authorities accused Russia of preventing the evacuation of people from the heavily besieged port city of Mariupol in the south of the country. Conditions in the city are dire, with civilians trapped there. Food, water and electricity are scarce.
More than 1,500 people have died in Mariupol from siege attacks so far, the Associated Press reported Sunday, citing the mayor's office.
Ukraine President Volodomyr Zelenskyy said at a Saturday news conference that about 1,300 Ukrainian soldiers have been killed since Russia's invasion began.
The Kremlin escalated its threats to the West as well. Speaking to Russia's state-controlled media on Saturday, Deputy Foreign Minister Sergey Ryabkov warned that Western convoys shipping weapons to Ukraine's defenders are "legitimate targets."