Russia's main mercenary group announced plans on Friday to withdraw from the eastern Ukrainian city of Bakhmut, but Ukraine said the fighters were reinforcing positions to try to seize it before Russia marks World War Two Victory Day next week.
Wagner Group leader Yevgeny Prigozhin said his men had been starved of ammunition and would expect the army to take their place in Bakhmut next Wednesday, jeopardising what has long been Russia's main target in its attempt to carve up its neighbour.
"My lads will not suffer useless and unjustified losses in Bakhmut without ammunition," Prigozhin said in a video accompanying a written withdrawal announcement addressed to military leaders including President Vladimir Putin.
The announcement said "bureaucrats" had held back supplies despite knowing that Wagner's target date to capture the city was May 9, the day of the World War Two commemoration.
"If, because of your petty jealousy, you do not want to give the Russian people the victory of taking Bakhmut, that's your problem," Prigozhin added in the video.
State-owned RIA news agency later reported that Russian Defence Minister Sergei Shoigu had instructed one of his deputy ministers to ensure troops had all the weapons they needed.
The battle for Bakhmut, which Russia sees as a stepping stone to other cities in Ukraine's Donbas region still beyond its control, has been the most intense of the conflict, costing thousands of lives on both sides in months of grinding warfare.
Ukrainian troops have been pushed back in recent weeks but have clung on in the city to inflict as many Russian losses as possible ahead of Kyiv's planned big push against the invading forces along the 1,000 km (620 mile) front line.
Ukraine's Armed Forces General Staff said in an evening report that Ukrainian forces repelled more than 30 attacks on the main sectors of the front line on Friday, with Bakhmut and Maryinka to the south seeing the heaviest fighting.
Pavlo Kyrylenko, governor of Donetsk region, said on the Telegram messaging app that Russian missiles had struck a heavy machinery manufacturing plant in the town of Kramatorsk and a home furnishing factory in the town of Sloviansk. He said there were no injuries in either attack.
Both towns are west of the front in and around Bakhmut.
Reuters pictures and video from Kramatorsk showed the machinery plant heavily damaged with windows blown out, facades torn off and top floors reduced to a twisted mass of metal and other building materials.
"Because of the lack of ammunition, our losses are increasing exponentially every day," Prigozhin's statement said. His fighters would be obliged to hand over their positions in Bakhmut to defence ministry units on May 10 and then withdraw to logistics camps "to lick our wounds", he added.
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