Russia is now in control of much of Severodonetsk, the epicenter of the battle for Ukraine’s eastern Donbas region

Russian forces are now in control of most of Severodonetsk, the epicenter of the bloody battle for Ukraine’s eastern Donbas region.

Street fighting continued to rage on Saturday in the eastern city, where Russian soldiers and Ukrainian troops are still locked in battle.

“The situation remains difficult. Fighting continues, but unfortunately, most of the city is under Russian control. Some positional battles are taking place in the streets,” said Serhiy Haidai, the governor of Luhansk region, which makes up Donbas along with the neighboring Donetsk region.

The most active areas of fighting were Severodonetsk, Popasna, and the area of the Siverskyi Donets river, Haidai said on national television Saturday, adding Russian forces were using “highly destructive thermobaric rocket artillery.”

“Unfortunately, enemy artillery is simply dismantling floor-to-floor buildings that are used as shelters. In this sense, it is difficult because the enemy will be knocked out of one street, and then they will start dismantling neighborhoods house by house with tanks, artillery and grads,” forcing Ukrainian forces in Severodonetsk to continuously move to new positions and regroup, the governor said.

In his nightly address Saturday, Ukrainian President Volodymyr Zelensky praised Ukrainian forces in the region, saying he was “proud of our defenders who could stop the advance of these hostile people, these occupiers, for many weeks and keep our defense strong.”

Zelensky has said the fight for the strategic city may dictate the outcome of the war in the east of the country.

“Severodonetsk remains the epicenter of the confrontation in Donbas,” Zelensky said earlier in the week.

“This is a very fierce battle, very difficult … Probably one of the most difficult throughout this war,” he added. “In many ways, the fate of our Donbas is being decided there.”

Severodonetsk lies in the heart of Donbas, a sprawling industrial region in eastern Ukraine that has seen intermittent fighting since 2014, when Russian-backed separatists seized control of two territories there – the self-declared Donetsk People’s Republic and Luhansk People’s Republic.

Haidai said Saturday Ukraine were still in control of the Azot chemical plant in Severodonetsk, where 800 people are reportedly sheltering, after a Russian-backed official claimed Ukrainian fighters were also trapped there.

“The story about the blockade of the Azot plant is a complete lie spread by Russian propagandists,” Haidai said on the Telegram messaging app.

Rodion Miroshnik, a Russian-backed leader of the self-proclaimed Luhansk People’s Republic, claimed Saturday up to 400 Ukrainian fighters were taking refuge in the factory complex, hiding alongside civilians in bomb shelters, and negotiations for their surrender and the safe evacuation of civilians were ongoing.

“The combatants are trying to make demands, namely to allow them to leave the territory of the chemical plant together with the hostages and to provide a corridor to go to Lysychansk. Such demands are unacceptable and will not be taken into consideration,” Miroshnik said.

Ukrainian soldiers talk during heavy fighting against Russia at the front line in Severodonetsk on June 8, 2022.

Death toll climbs in Mariupol

Further south in Mariupol, an additional 24 deaths of children were reported by Ukraine’s Prosecutor General’s Office on Saturday, following Russian shelling during a monthslong siege in the southern port city.

The blockade ended last month after Russian forces took control of the Azovstal steel plant where Ukrainian forces had holed up.

This brings the total death toll of minors during Russia’s invasion of Ukraine to 287, the Prosecutor General’s Office said in a Telegram post. More than 492 children have been injured during the war, according to the statement.

The statement added the figures are not complete, as work is underway to verify the deaths of children in other places where there is active fighting.

Fresh graves are seen at a cemetery in the city of Mariupol on June 2, 2022.

The office also said 1,971 educational institutions have been damaged by Russian bombardments, with 194 of them having been completely destroyed.

On May 25, an adviser to Mariupol’s mayor, Petro Andrushchenko – who has also moved to Ukrainian-held territory – told CNN Mariupol town hall officials believe at least 22,000 residents of the city were killed during three months of war.

The news comes as the city is battling a potential cholera outbreak, according to a British intelligence report published on Friday.

Access to drinking water, internet connection and phone services are unreliable in Russian-occupied areas of Ukraine, the report said, reflecting concerns of Ukrainian officials as Russia scrambles to provide basic public services to civilian populations in areas it has occupied.

In Saturday’s nightly address, Zelensky said “about 32,000” Russian troops have been killed since the start of the invasion. Earlier Saturday, the Ukrainian military said total Russian combat losses since February 24 were “about 32,050.”

CNN cannot independently verify Ukraine’s figures on the number of Russian forces killed in the conflict and the exact death toll remains unclear.

‘Ukraine will definitely prevail’

A satellite image shows damaged buildings near Chemist's Palace of Culture in downtown Severodonetsk on June 6, 2022.

As Russian forces advance their control of key regions in Ukraine, and the number of civilian casualties rise, Zelensky has remained firm in his stance that Ukraine will overcome Russia’s invasion.

Speaking in a special virtual address to the Shangri-La Dialogue, Asia’s premier defense conference, Zelensky said Ukraine will “definitely prevail” in its war against Russia.

“This is the confrontation between the possible, which we and many people in the world need, and the impossible, for which Russia is so desperately fighting for,” Zelensky said.

He added Russia regarded his country as its “colony” and was doing its utmost to make it impossible for Ukraine to “exist freely and independently.”

Smoke rises in the city of Severodonetsk during heavy fighting. Russia has made capturing the city its current priority, according to Ukrainian military officials.

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“Russia wishes to make it impossible for our people to use their land, resources and water in their best interest. Russia wishes to steal it, and this active looting of the territory it has (managed) to occupy – they are taking away literally everything,” Zelensky added.

“It is on the battlefield in Ukraine that the future rules of this world are being decided along with the boundaries of the possible,” Zelensky said.

“Let us save the whole world from coming back to the times when everything was decided based on the so-called right of might and when certain peoples and their ideas, and many nations, were of no consequence,” Zelensky said.

Ukraine’s president also urged leaders to do whatever is needed to “break the ability of Russia and any other country in the world to block seas and destroy freedom of navigation.”

A satellite image shows a closeup of bulk carrier ship loading grain at the port of Sevastopol, Crimea May 19, 2022. Picture taken May 19, 2022. Satellite image 2022 Maxar Technologies/Handout via REUTERS ATTENTION EDITORS - THIS IMAGE HAS BEEN SUPPLIED BY A THIRD PARTY. MANDATORY CREDIT. NO RESALES. NO ARCHIVES. DO NOT OBSCURE LOGO.

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Zelensky warned failure to do so would result in an “acute and severe food crisis and famine” in many Asian and African countries. He added the Black Sea, through which Ukraine exported most of its foodstuffs before Russia’s invasion, has become the most dangerous waterway in the world.

Since the war began, Russia has been blocking Ukraine from exporting goods from its ports, fueling fears of a global food crisis.

Before the war, wheat supplies from Russia and Ukraine accounted for almost 30% of global trade, and Ukraine was the world’s fourth-largest exporter of corn and the fifth-largest exporter of wheat, according to the US State Department. The United Nations World Food Program – which helps combat global food insecurity – buys about half of its wheat from Ukraine each year and has warned of dire consequences if Ukrainian ports are not opened up.

“Ladies and gentlemen, I am grateful for your support to Ukraine, I am grateful for your attention to Ukraine, to our country. But please remember that this support and this attention is not only for Ukraine, but for you as well,” Zelensky said.

CNN’s Kostan Nechyporenko, Jonny Hallam, Masha Angelova, Joshua Berlinger and Mariya Knight contributed to the reporting.