Russian President Vladimir Putin on Saturday hailed his army's capture of the town of Avdiivka in the Donetsk People's Republic (DPR) as an "important victory", following a hasty withdrawal by the Ukrainian forces.

"The President congratulated our military and fighters on such an important victory, on such a success," Kremlin spokesperson Dmitry Peskov told state news agencies.

Russian Defense Minister Sergei Shoigu informed Putin about the achievement in a meeting at the Kremlin, his ministry said in a statement.

Avdiivka was a "powerful defensive hub" for Ukraine's armed forces and its capture would "move the front line away from Donetsk," reducing Ukraine's ability to shell the Russian stronghold, the Defense Ministry said.

The losses of Ukrainian troops in the battle for Avdiivka amounted to over 1,500 servicepeople over the past 24 hours, the Ministry also highlighted.

Kiev had earlier announced the withdrawal of its forces from the town, which it said was taken to reduce military casualties at a time of stretched resources.

"At the moment, measures are being taken to finally clear the town of militants and to block the Ukrainian units that have left the town and are holed up in the Avdiivka coke plant" to the north, the Russian Defense Ministry pointed out.

In a related context, Ukrainian military commander of the Tavria operational group, Oleksandr Tarnavskyi, admitted on Saturday that a number of Ukrainian troops had been captured during retreat from their stronghold in Avdiivka.

"The withdrawal of personnel from Avdiivka took place in accordance with a plan designed with consideration of different scenarios and a possible change in the operational situation. And yet, at the final stage of the operation, under pressure from superior enemy forces, several Ukrainian servicepeople were captured," Tarnavskyi said in a statement quoted by the Ukrainian newspaper Strana.

Biden blames lawmakers' 'inaction' for Kiev's loss in Avdiivka 

US President Joe Biden on Saturday blamed congressional inaction for Russia's capture of Avdiivka, as partisan wrangling holds up $60 billion in badly needed military aid.

With Ukrainian forces running low on supplies, Biden called Ukrainian President Volodymyr Zelensky on Saturday "to underscore the United States' commitment to continue supporting Ukraine," according to a White House statement summarizing the call.

It said the Ukrainian withdrawal from Avdiivka came "after Ukrainian soldiers had to ration ammunition due to dwindling supplies as a result of congressional inaction, resulting in Russia's first notable gains in months."

Biden "reaffirmed the strong bipartisan support in the US government and among the American people for Ukraine's sovereignty and territorial integrity," and he called on Congress to urgently pass a spending bill including aid for Ukraine.

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