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Ukrainian fighters holed up in a steel plant in the last known pocket of resistance inside the shattered city of Mariupol ignored an ultimatum from the Russians to surrender or die on Sunday.
The fall of Mariupol, the site of a merciless, seven-week siege that has reduced much of the city to a smoking ruin, would be Moscow’s biggest victory of the war yet.
It would free up troops to take part in a potentially climactic battle for control of Ukraine’s industrial east.
As its missiles and rockets slammed into other parts of the country, Russia estimated 2,500 Ukrainian troops and about 400 foreign fighters were dug in at the Azovstal steel mill, which covers more than 11 square kilometres and is laced with tunnels.
Moscow gave the defenders a midday deadline to surrender, saying those who laid down their arms were “guaranteed to keep their lives". The Ukrainians rejected it, as they did with previous ultimatums.
“We will fight absolutely to the end, to the win, in this war,” Ukrainian Prime Minister Denys Shmyhal vowed on ABC’s This Week.
He said Ukraine was prepared to end the war through diplomacy if possible, “but we do not have intention to surrender".
Ukrainian President Volodymyr Zelenskyy sent Easter greetings on Twitter, saying: “The Lord’s resurrection is a testimony to the victory of life over death, good over evil.”
If Mariupol falls, Russian forces are expected to join an all-out offensive in the coming days for control of the Donbas, the eastern region that the Kremlin is bent on capturing after failing to take Kyiv, Ukraine’s capital.
The relentless bombardment and street fighting in Mariupol have killed at least 21,000 people, by the Ukrainians’ estimate.
A maternity hospital was hit by a lethal Russian airstrike in the opening weeks of the war, and about 300 people were reported killed in the bombing of a theatre where civilians were taking shelter.
An estimated 100,000 stayed in the city from a pre-war population of 450,000, They are trapped without food, water, heat or electricity in a siege that has made Mariupol the scene of some of the worst suffering of the war.
“All those who will continue resistance will be destroyed,” said Maj Gen Igor Konashenkov, the Russian Defence Ministry spokesman.
Ukrainian Deputy Defence Minister Hanna Malyar said Mariupol was a “shield defending Ukraine” as Russian troops prepare for battle in the mostly Russian-speaking Donbas, where Moscow-backed separatists already control some territory.
Russian forces, meanwhile, carried out aerial attacks near Kyiv and elsewhere to weaken Ukraine’s military before the anticipated assault.
After the humiliating sinking of the flagship of Russia’s Black Sea Fleet last week in what the Ukrainians said was a missile attack, the Kremlin had vowed to step up strikes on the capital.
Russia said on Sunday that it had attacked an ammunition plant near Kyiv overnight with precision-guided missiles, the third such strike in as many days.
Explosions were also reported overnight in Kramatorsk, the eastern city where rockets this month killed at least 57 people at a train station crowded with civilians trying to move out before the Russian offensive.
A regional official in eastern Ukraine said at least two people were killed when Russian troops fired at residential buildings in the town of Zolote, near the front line in the Donbas.
At least five people were killed by Russian shelling in Kharkiv, Ukraine’s second-largest city, on Sunday, regional officials said.
The barrage slammed into apartment buildings and left the streets scattered with broken glass and other debris, including part of at least one rocket.
Russia also said that its forces shot down two Ukrainian MiG-29 fighter jets in the Kharkiv region and destroyed two command posts and a radar system for S-300 surface-to-air missiles in the city of Avdiivka, north of Donetsk city.
Ukrainian officials did not immediately confirm the losses.
Ms Malyar said the Russians continued to hit Mariupol with air strikes and could be preparing for an amphibious landing to reinforce their ground troops.
Capturing the southern city on the Sea of Azov would allow Russia to fully secure a land corridor to the Crimean Peninsula, which it seized in 2014, and deprive Ukraine of a major port and its prized industrial assets.
The looming offensive in the east, if successful, would give Russian President Vladimir Putin a vital piece of the country and a badly needed victory that he could give to the Russian people amid the war’s mounting casualties and the economic hardship caused by the West’s sanctions.
Austrian Chancellor Karl Nehammer, who met Mr Putin in Moscow last week — the first European leader to do so since the invasion February 24 — said the Russian president is “in his own war logic” on Ukraine.
Mr Nehammer told NBC he thought Mr Putin believed he was winning the war, and “we have to look in his eyes and we have to confront him with that, what we see in Ukraine".
Without explicitly mentioning Mr Putin’s decision to invade, Pope Francis made an anguished Easter Sunday plea for peace in Ukraine, decrying “this cruel and senseless war into which it was dragged".