Russian forces are making further advances in street fighting in the eastern Ukrainian city of Kostiantynivka in the Donetsk region, the Defence Ministry in Moscow said on Sunday.
Forces have brought a further 100 or more buildings in the city under Russian control, the Moscow ministry said. In the south-west of the city, encircled units of the Ukrainian armed forces had been destroyed, it said.
Ukraine's military had recently acknowledged it was facing a difficult situation in the city.
The US-based Institute for the Study of War (ISW) in Washington said in an analysis that Ukraine's ability to defend Kostiantynivka was deteriorating. At the same time, the experts said that Moscow was using its detailed statements to create a greater impression of Russian presence than actually existed.
Kiev's leadership had recently been saying that it had halted the Russian advance and recaptured territory. Yet even Ukrainian maps show Russian forces advancing into the heavily destroyed industrial city, albeit more slowly than during the winter months.
Independent military observers consider it possible that Kostiantynivka could fall during the coming months. Putin would then be closer to his goal of bringing the Donbas completely under Russian control.
Of the larger cities in the Donetsk region, only Sloviansk, Kramatorsk and Druzhkivka would then remain under Ukrainian control.
The Russian Defence Ministry said that the advance of Moscow's forces into Kostiantynivka had prompted Ukraine to evacuate key facilities in the nearby cities of Kramatorsk and Druzhkivka.
Putin has said that complete control of the Donetsk region is a central war aim and a precondition for ceasefire negotiations. The Russian president has been waging a destructive war against Ukraine for more than four years.
