With Russia’s big offensive said to be underway, fresh battles rock eastern Ukraine

Moscow again on Tuesday demanded the surrender of holdout Ukrainian forces in the besieged southern port of Mariupol and bombardment boomed across the country’s east in what Russia and Ukraine are calling a major new phase of the ferocious nearly 8-week-old war.

Although Ukraine says Russia has begun its long-expected all-out assault in the east – and Moscow’s top diplomat confirmed Tuesday the struggle has entered its next stage — some Western military officials and analysts suggest the current attacks are only a prelude to a larger and potentially far more brutal offensive.

President Biden was to confer Tuesday with key allies about the next phase of the war and how the West will respond.

Ukrainian authorities, meanwhile, implored civilians to get out of the eastern battle zone by any means possible, but acknowledged that for a third straight day there had been no agreement reached with Russia to set up humanitarian corridors those fleeing the fighting could use for safe passage.

The latest Russian ultimatum to the Ukrainian forces in Mariupol came in a statement by the defense ministry in Moscow promising that those who lay down their arms “are guaranteed to remain alive.” But as happened over the weekend, the surrender deadline came and went without any sign of a Ukrainian pullback from a sprawling steelworks plant where fighters and hundreds of civilians are holed up in a network of tunnels.

A Ukrainian commander says Russia has been using “bunker-buster” bombs to try to dislodge the defenders.

Mariupol’s capture would likely be hailed by Russia as a pivotal triumph in a war that has yielded few of those for Moscow. It would free up more brigades for the eastern fight, as well as enable the creation of a strategically important land corridor between Russian-controlled areas and the annexed Crimean Peninsula.

Moscow was initially silent on Monday night when Zelensky declared that the war for Ukraine’s industrial east, known as the Donbas, had begun. The area is made up of two large regions, Luhansk and Donetsk, parts of which are already controlled by Russia-backed separatists.

“We will fight,” the Ukrainian leader vowed in his nightly video address. “We will defend ourselves.”

Russian appeared to confirm the wider offensive’s start when Foreign Minister Sergei Lavrov said in an interview broadcast Tuesday that “another stage of this operation is beginning.”

“I am sure this will be a very important moment of this entire special operation,” Lavrov told Indian television. Russia refers to Europe’s biggest land war since World War II as a “special military operation.”

Ukraine’s military said Tuesday that Russia’s apparent aim was to seize full control of the Donbas. Its general staff said in a statement that overnight and early Tuesday, “the occupiers made an attempt to break through our defenses along nearly the entire frontline,” a distance of more than 300 miles.

All along the battlefront, Russian forces were probing for “sensitive spots” in Ukraine’s defense, presidential adviser Oleksiy Arestovych said. But speaking on national television, he predicted the offensive would fail because the Russians “simply do not have enough strength.”

Even so, civilian casualties were mounting. Luhansk regional governor Serhiy Haidai said on Ukrainian television that the town of Kreminna came under heavy artillery fire overnight, setting residential buildings ablaze.

The Ukrainians retreated in order to regroup, giving Russia control of the town, because “it simply makes no sense to stand in one place, to die” without prospects for inflicting any real harm on the invaders, he said.

In the northeasterncity of Kharkiv, hammered by near-constant bombardment, five people had been killed by shelling in the last 24 hours, the regional governor said Tuesday.

For many in the battle zone, there’s no clear distinction between a much-heralded new phase of fighting and what has already occurred during the nearly two months since Russia invaded its smaller neighbor.

In Avdiivka, less than two miles away from the separatist-controlled city of Donetsk, shelling had been a constant backdrop, with many forced to live their lives largely underground. In one school, some 200 people took shelter in the dank confines of the basement level, sleeping on mattresses laid over desks. They shared one bathroom, on the ground level.

A month ago, an artillery round smashed the fourth-floor apartment of the head of Avdiivka’s utility company, who gave only his first name, Rostislav, for reasons of privacy.

His family – a wife and three children, the youngest seven months old — found safety in the Black Sea city of Odessa. But the shelling stole away a home whose purchase had cost him all he had.

“I’m 37, and I have nothing,” he said.

Standing in front of the ruined apartment building, he pointed out where the shell had hit, debris now in an organized pile on the side of the street. Nearby were gouges and craters in the sidewalk where other artillery rounds had fallen.

Despite Avdiivka’s proximity to the front lines of the eight-year war between Russian-backed separatists and Ukrainian forces, Rostislav described a community that flourished before the Feb. 24 invasion.

“There was work, money and happiness,” he said. Now, like so many other cities across the Donbas, it was virtually a ghost town.

Asked if he planned to leave, he sighed a deep sigh.

“Not today,” he said.

Bulos reported from Avdiivka, Ukraine and King from Berlin.

This story originally appeared in Los Angeles Times.