Wagner Group chief Yevgeny Prigozhin said Russia needs to desperately provide his troops with ammunition. Meanwhile, Ukraine urged more German military aid.
The head of Russia's mercenary Wagner Group threatened to withdraw his troops from the embattled city of Bakhmut in Ukraine amid heavy casualties.
Yevgeny Prigozhin told military blogger Semyon Pegov losses were five times higher than necessary because of the lack of artillery ammunition.
"Every day, we have stacks of thousands of bodies that we put in coffins and send home," Prigozhin said in the interview published on Saturday.
He had written to Russian Defense Minister Sergei Shoigu asking for supplies. "If the ammunition deficit is not replenished, we are forced, in order not to run like cowardly rats afterwards, to either withdraw or die."
Wagner has been spearheading Russia's assault on Bakhmut but Ukrainian defenders have been able to hold onto part of the city.
Casualties are high on both sides.
Prigozhin had previously claimed that the Russian military was withholding ammunition from his soldiers.
He charged ammunition stockpiles were withheld because of "treason" by Russian officials.
Last week he expressed concern about a counter-attack by well-equipped Ukrainian troops at Bakhmut.