Russian forces have launched an all-out assault to encircle Ukrainian troops in twin cities straddling a river in eastern Ukraine, a battle which could determine the success or failure of Moscow's main campaign in the east.
Exactly three months after Russia invaded Ukraine, authorities in the second-largest city Kharkiv were expected on Tuesday to open the underground metro, where thousands of civilians had sought shelter for months under relentless bombardment.
The reopening is a symbol of Ukraine's biggest military success over the past few weeks: pushing Russian forces largely out of artillery range of Kharkiv, as they did from the capital Kyiv in March.
But the decisive battles of the war's latest phase are still raging further south, where Moscow is attempting to seize the Donbas region of two eastern provinces, Donetsk and Luhansk, and trap Ukrainian forces in a pocket on the main eastern front.
The easternmost part of the Ukrainian-held Donbas pocket, the city of Sievierodonetsk on the east bank of the Siverskiy Donets river and its twin Lysychansk on the west bank have become the pivotal battlefield there, with Russian forces advancing from three directions to encircle them.
"The enemy has focused its efforts on carrying out an offensive in order to encircle Lysychansk and Sievierodonetsk," said Serhiy Gaidai, governor of Luhansk, where the two cities are among the last territory still held by Ukraine.
"The intensity of fire on Sievierodonetsk has increased by multiple times, they are simply destroying the city," he said on TV, adding there were about 15,000 people in the city and the Ukrainian military remains in control of it.
Reuters journalists in the Donbas, who reached Bakhmut further west, heard and saw intense shelling on the highway towards Lysychansk on Monday. Ukrainian armoured vehicles, tanks and rocket launchers were moving towards the front lines, with and buses carrying soldiers.
Further west in Slovyansk, one of the biggest Donbas cities still in Ukrainian hands, air raid sirens wailed on Tuesday morning but streets were still busy, with a market full, children riding on bikes and a street musician playing violin by a supermarket.
Two empty public transport buses were driving towards the frontline town of Lyman to evacuate civilians from heavy shelling there, escorted by police and a military car.
Gaidai said Ukrainian forces had driven the Russians out of the village of Toshkivka just to the south of Sievierodonetsk. That could not be independently confirmed. Four people had been killed in the shelling of one home in Sievierodonetsk overnight.
The battle there follows the surrender last week of Ukraine's garrison in the port of Mariupol after nearly three months of siege in which Kyiv believes tens of thousands of civilians have died.
Russia is now in control of an unbroken swathe of eastern and southern Ukraine, but has yet to achieve its objective of seizing all of Luhansk and Donetsk.
US President Joe Biden, meeting the leaders of Japan, India and Australia in Tokyo, said the war showed the importance of defending international law and human rights around the world. The previous day he broke with convention to say openly that the United States would use its military to protect Taiwan, the self-ruled island claimed by China.
Biden's remarks on Taiwan were seen as a sign of how three months of what Washington and its allies describe as an unprovoked Russian war of aggression in Ukraine have invigorated Western resolve on security issues.
Russia's three-month long invasion, the biggest attack on a European state since 1945, has seen more than 6.5 million people flee abroad, turned entire cities into rubble and brought down severe economic sanctions on Moscow.
Australian Associated Press
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