Over 1.2 million refugees have fled Ukraine in the week since Russia's invasion
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While laying siege to Mariupol for days, Russian forces also cut its electricity, food, water, heating and transportation in the depths of winter, prompting comparisons to the Nazi blockade of Leningrad in World War II.
"For now, we are looking for solutions to humanitarian problems and all possible ways to get Mariupol out of the blockade," said mayor Vadim Boychenko. He called for a ceasefire and a humanitarian corridor for food and medicine.
Since President Vladimir Putin's army invaded on February 24, Russia has pummelled Ukrainian cities, killed hundreds of civilians and assaulted Europe's largest atomic power plant.
The invasion has drawn condemnation and severe sanctions from Western nations balancing punishment of the Kremlin with fears of a hazardous escalation. Moscow has seized two key cities in its 10-day-long invasion, Berdiansk and Kherson on Ukraine's southern Black Sea coast.
But capturing Mariupol, a city of about 450,000 people on the Azov Sea, would represent a bigger prize for Russian forces as it would deal a severe blow to Ukraine's maritime access and connect troops coming from annexed Crimea and the Donbas.
Kremlin spokesperson Dmitry Peskov said Moscow was waiting for a third round of talks with Ukraine in Belarus, and one of Kyiv's negotiators said it hoped to hold them this weekend.
Ukrainian President Volodymyr Zelensky is set to appeal to Washington for more assistance today. He will address the US Senate as some lawmakers urged President Joe Biden to take tougher measures, including banning Russia's oil imports.
In the northern city Chernihiv, 47 people died on Thursday when Russian forces bombed residential areas, including schools and a high-rise apartment block, according to local officials.
"We are faced together with what is President Putin's war of choice, unprovoked, unjustified, and a war that is having horrific, horrific consequences," US Secretary of State Antony Blinken said in Brussels.
With fears growing of nuclear conflict, the US and Russian armed forces have set up a new direct phone line to reduce the risks of "miscalculation," the Pentagon said. Russian forces attacked and seized the Zaporizhzhia nuclear plant on Friday, pushing Kyiv to accuse Moscow of "nuclear terror".
