The Wagner mercenary group, fighting on behalf of Russia in Ukraine, has said it will pull out of Bakhmut next week due to a lack of ammunition.
The Wagner Group is controlled by founder Yevgeny Prigozhin, an oligarch with reportedly close links to President Putin, and has been used by Russia throughout their invasion of Ukraine.
Mr Prigozhin has now branded Russian commanders cowards and accused them of starving his troops of supplies as they were thrown into what he called the meatgrinder of Bakhmut.
He went on to claim the Russian military was jealous of his men's success and wanted victory for themselves, saying they'd cut supplies to the Wagner Group in order to make sure they failed.
He also said the Russian military was providing his mercenaries with just a tenth of the ammo they needed.
It comes after weeks of bitter and bloody fighting, with Russian President Vladimir Putin ordering Bakhmut to be taken by 9 May to coincide with Russia's Victory Day parade – which marks the Soviet Union's victory over Nazi Germany.
However, weeks of bloody and bitter fighting have resulted in Russia failing to take all of Bakhmut.
Wagner fighters, many of them former convicts, led the assault – with the US Government claiming 100,000 Russian troops have been wounded or killed since December, with half of them Wagner fighters.
Ukraine sees Bakhmut as a symbol of resistance, and a way to kill as many Russian troops as possible ahead of its expected counter-offensive.
The head of the Wagner Group's public condemnation of Russia's military comes after months of jabbing between the two.
While the Kremlin is increasingly keen to contain his influence, it is unclear whether he'll do as he says and pull his men out.
The UK's Ministry of Defence said in April, Russia is likely looking to "sponsor and develop" alternative companies to eventually replace the Wagner Group in Ukraine.
Regardless, the outburst shows an embarrassing internal rift for President Putin.