Civilians have fled areas of eastern Ukraine ahead of an anticipated Russian offensive, while Kyiv says it’s checking reports that Russian forces used chemical weapons in the besieged port city of Mariupol.

The battle for Mariupol was reaching a decisive phase, with Ukrainian marines holed up in the Azovstal industrial district.

Should the Russians seize Azovstal, they would be in full control of Mariupol, the linchpin between Russian-held areas to the west and east. The city has already been laid waste by weeks of Russian bombardments that have killed possibly thousands of civilians.

Deputy Defence Minister Hanna Malyar said the government was checking unverified information that Russia may have used chemical weapons while besieging Mariupol.

“There is a theory that these could be phosphorous munitions,” Malyar said in televised comments.

President Volodymyr Zelenskiy had said on Monday night that Russia could resort to chemical weapons as it amassed troops in the eastern Donbas region for a new assault on Mariupol. He did not say if they actually had been used.

The United States and Britain said they were trying to verify the reports. If Russia had used chemical weapons, “all options were on the table” in response, British Junior Defence Minister James Heappey said in London on Tuesday.

Russian-backed separatist forces in the east denied using chemical weapons in Mariupol, the Interfax news agency reported.

But should it prove to be the case, it would mark a dangerous new development in a war that has already left a trail of death of destruction since Russian President Vladimir Putin sent his troops over the border on February 24.

About a quarter of Ukraine’s 44 million population have been forced from their homes, cities turned into rubble, and thousands of people have been killed or injured – many of them civilians.

Putin calls the action a “special military operation” to demilitarise and “denazify” Ukraine but it has drawn condemnation and alarm in the West, which has imposed a wide range of sanctions to squeeze the Russian economy.

After their troops got bogged down in the face of Ukrainian resistance, the Russians abandoned their bid to capture the capital Kyiv. But they are redoubling their efforts in the east and Ukrainian forces are digging in to face a new offensive.

The governor of Luhansk region, Serhiy Gaidai, urged residents to leave using five humanitarian corridors agreed for the east.

In all, nine humanitarian corridors had been agreed for Tuesday, including one for private cars from Mariupol, Deputy Prime Minister Iryna Vereshchuk said.

The General Staff of Ukraine’s Armed Forces said that other than Mariupol, Russian forces were also intent on capturing Popasna, a town west of Luhansk, and were set to launch an offensive in the direction of Kurakhove, in the Donetsk region.

The Ukrainian military said its troops had repulsed attacks in both Luhansk and Donetsk.

Zelenskiy pleaded overnight for more weapons from the West to help it end the siege of Mariupol and fend off the expected Russian offensive in the east.

The departure of Russian forces from the outskirts of Kyiv brought to light allegations of war crimes including executions and rape of civilians. Moscow dismisses the allegations as Ukrainian and Western provocations and has also accused Ukrainian forces of sexual violence.

Senior UN official Sima Bahous told the UN Security Council on Monday that while all allegations must by independently investigated, “the brutality displayed against Ukrainian civilians has raised all red flags”.

“We are increasingly hearing of rape and sexual violence,” she said.

Kateryna Cherepakha, president of rights group La Strada-Ukraine, told the council via video: “Violence and rape is used now as a weapon of war by Russian invaders in Ukraine.”

Russia’s deputy UN ambassador denied the allegations and accused Ukraine and allies of “a clear intention to present Russian soldiers as sadists and rapists”.

Putin is meeting Belarusian President Alexander Lukashenko on Tuesday to discuss Ukraine and Western sanctions. Belarus is a key staging area for Russian forces.

AAP

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