Zelenskyy: 'Russia has driven almost everyone and everything capable of fighting us against Ukraine'
Russia has hurled its military might against Ukrainian cities and towns and poured more troops into the war, as it bombards the country's entire eastern defence line.
Fighting has unfolded along a 300-mile boomerang-shaped front, in what is known as the Donbas.
If successful, it would give President Vladimir Putin a victory following the failed attempt by Moscow's forces to storm the capital, Kyiv, and heavier-than-expected casualties.
Watch ITV News Correspondent Peter Smith's report on the battle for Donbas
Both sides have described the assault that began on Monday as a new phase of a war that, according to the United Nations, has forced over five million people to flee Ukraine.
The nation's president, Volodomyr Zelenskyy, warned in his latest overnight address: "They have driven almost everyone and everything that is capable of fighting us against Ukraine".
The fight for Mariupol, the devastated port city in the Donbas, continues as Ukrainian troops said Russian military dropped heavy bombs to flatten what was left of a sprawling steel plant, believed to be the defenders' last holdout, and hit a hospital where hundreds were staying.
The Ukrainian General Staff said defeating the last resistance in the Azovstal steel mill in Mariupol remains Russia’s top priority.
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A few thousand Ukrainian troops, by the Russians’ estimate, remained holed up in the plant, representing what was believed to be the last major pocket of resistance in the city.
Russia issued a new ultimatum to the Ukrainian defenders to surrender on Wednesday after a previous ultimatum was ignored. The Russian Defence Ministry said those who surrender will be allowed to live and given medical treatment. There was no immediate response from the Ukrainian troops, but they have repeatedly vowed not to give up.
Ukrainian deputy prime minister Iryna Vereshchuk said the two sides have agreed on a humanitarian corridor for the city. It will evacuate women, children and the elderly from Wednesday afternoon local time, she added.
Mariupol's mayor, Vadym Boychenko, urged residents to leave the city, but his deputy, Sergii Orlov said he did not trust Russia to provide safe passages out.
Mariupol's deputy mayor on humanitarian corridors: 'I do not believe in any trust from Russia'
Meanwhile in the east, the cities of Kharkiv and Kramatorsk came under deadly attack. Russia also said it struck areas around Zaporizhzhia and Dnipro west of the Donbas with missiles.
Despite claims that they are hitting only military sites, the Russians continue to target residential areas and kill civilians, President Zelenskyy said.
"The Russian army in this war is writing itself into world history forever as the most barbaric and inhuman army in the world," he said.
According to Britain's Ministry of Defence, Russian attacks on cities across Ukraine are an attempt to disrupt the movement of Ukrainian reinforcements and weapons to the east.
Associated Press journalists in Kharkiv said at least four people were killed and three wounded in a Russian attack on a residential area of the city. An explosion also rocked Kramatorsk, killing at least one person and wounding three, according to AP journalists at the scene.
In the southern city of Bashtanka, an unspecified number of people were wounded when Russian forces shelled the hospital, destroying the reception area and the dialysis unit, the head of the regional council, Hanna Zamazeeva, said on Facebook.
Russia's Defence Ministry said that overnight, Moscow's forces had bombarded 73 Ukrainian military sites, including troop concentrations and missile-warhead storage depots, in or near several cities or villages.
Those claims could not be independently verified.
A Russian victory in the Donbas would deprive Ukraine of the industrial assets concentrated there, including mines, metals plants and heavy-equipment factories.
President Joe Biden is expected to announce a new weapons package for Ukraine in the coming days, a US official speaking anonymously said it will include additional artillery and ammunition.
Canada, Norway and the Netherlands also plan to send more heavy weapons, their prime ministers said.