Russia-Ukraine war: Ukraine thwarts Russian advances; fight rages for Mariupol

Ukrainian forces fought off continuing Russian efforts to occupy Mariupol and claimed to have retaken a strategic suburb of Kyiv on Tuesday, mounting a defense so dogged that it is stoking fears Russia's Vladimir Putin will escalate the war to new heights.

"Putin's back is against the wall," said US President Joe Biden, who is heading to Europe this week to meet with allies. "And the more his back is against the wall, the greater the severity of the tactics he may employ."

Biden reiterated accusations that Putin is considering resorting to using chemical or biological weapons, though Pentagon spokesman John Kirby said the US Has seen no evidence to suggest that such an escalation is imminent.

The warnings came as attacks continued in and around Kyiv and Mariupol, and people escaped the battered and besieged port city.

The hands of one exhausted Mariupol survivor were shaking as she arrived by train in the western city of Lviv.

"There's no connection with the world. We couldn't ask for help," said Julia Krytska, who was helped by volunteers to make it out with her husband and son. "People don't even have water there."

Explosions and bursts of gunfire shook Kyiv, and heavy artillery fire could be heard from the northwest, where Russia has sought to encircle and capture several of the capital's suburban areas.

Early Tuesday, Ukrainian troops drove Russian forces from the Kyiv suburb of Makariv after a fierce battle, Ukraine's Defense Ministry said. The regained territory allowed Ukrainian forces to retake control of a key highway and block Russian troops from surrounding Kyiv from the northwest.

A video posted by Ukrainian police showed them surveying damage in Makariv, including to the town's police station, which an officer says took a direct hit to its roof. The police drove by destroyed residential buildings and along a road pocked by shelling. The town appeared all but deserted.

Still, the Defense Ministry said Russian forces partially took other northwest suburbs, Bucha, Hostomel and Irpin, some of which have been under attack almost since Russia invaded nearly a month ago.

A Western official, speaking on condition of anonymity to discuss military assessments, said Ukrainian resistance has brought much of Russia's advance to a halt but has not sent Moscow's forces into retreat.

"We have seen indications that the Ukrainians are going a bit more on the offensive now," Pentagon press secretary John Kirby separately told reporters in Washington. He said that was particularly true in southern Ukraine, including near Kherson, where "they have tried to regain territory."

Russia's far stronger, bigger military has many Western military experts warning against overconfidence in Ukraine's long-term odds. Russia's practice in past wars in Chechnya and Syria was to grind down resistance with strikes that flattened cities, killed countless civilians and sent millions fleeing.

But Russian forces appeared unprepared and have often performed badly against Ukrainian resistance. The US Estimates Russia has lost a bit more than 10 per cent of the overall combat capability it had at the start of the fight, including troops, tanks and other materiel.

Western officials say Russian forces are facing serious shortages of food, fuel and cold weather gear, leaving some soldiers suffering from frostbite. Ukrainians have reported hungry soldiers looting stores and homes for food.

The invasion has driven more than 10 million people from their homes, almost a quarter of Ukraine's population, according to the United Nations.
Thousands of civilians are believed to have died. Estimates of Russian military casualties vary widely, but even conservative figures by Western officials are in the low thousands.

On Monday, Russia's pro-Kremlin Komsomolskaya Pravda newspaper, citing the Defense Ministry, reported that almost 10,000 Russian soldiers had been killed. The report was quickly removed, and the newspaper blamed hackers. The Kremlin refused to comment. The Western official said the figure is "a reasonable estimate."

Facing unexpectedly stiff resistance that has left the bulk of Moscow's ground forces miles from the centre of Kyiv, Putin's troops are increasingly concentrating their air power and artillery on Ukraine's cities and civilians.

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Talks to end the fighting have continued by video. Ukrainian President Volodymyr Zelenskyy has said he would be prepared to consider waiving any bid by Ukraine to join NATO "a key Russian demand" in exchange for a cease-fire, the withdrawal of Russian troops and a guarantee of Ukraine's security.

UN Secretary-General Antonio Guterres said he saw progress in the talks. "From my outreach with various actors, elements of diplomatic progress are coming into view on several key issues," and the gains are enough to end hostilities now, he said. He gave no details.

The Western official, though, said that there were no signs Moscow was ready to compromise.