More than 20,000 Russian troops have died and another 80,000 were wounded in five months of fighting in eastern Ukraine, particularly in Bakhmut, a White House official said Monday (May 1).
"We estimate that Russia has suffered more than 100,000 casualties, including over 20,000 killed in action," National Security Council spokesman John Kirby told reporters.
"Russia's attempt at an offensive in the Donbas, largely through Bakhmut, has failed... Russia has been unable to seize any really strategically significant territory," Kirby said.
Kirby, citing newly declassified US intelligence, said that about half of those killed were soldiers recruited by the private military company Wagner, which draws much of its ranks from prison populations in Russia.
The toll from fighting -- with the most intense battle being for Bakhmut, where Ukrainian troops have been driven from all but a sliver of the city -- accounts for losses since the start of December, according to the US figures.
"This attempted effort, particularly in Bakhmut, has come at a terribly, terribly high cost. Russia has exhausted its military stockpiles and its armed forces," Kirby said.
Kirby said he was not giving estimates of Ukrainian casualties because "they are the victims here. Russia is the aggressor."
The White House will not put "information in the public domain that makes it any harder" for the close Western ally, whose army is being armed and trained by a US-led coalition of countries, he said.
Russia's casualties have effects that extend beyond the battlefield, say experts.
For a country already suffering from a shrinking labour force because of persistently low birth rates, the conflict means even more difficulties that could persist for years.
Russian authorities have not given updated estimates of troop losses in Ukraine since September 2022, when the Defence Ministry reported 5,937 dead.
"We don't know about the exact losses in the military operation, but 300,000 people were mobilised, further reducing the number of young people working," said Natalya Zubarevich, an expert at the Moscow State University.
The battlefield losses come on the heels of a deadly coronavirus pandemic, which "hit Russia hard", demographic expert Igor Yefremov told AFP.
Official figures count around 400,000 deaths from COVID-19, but the actual toll is estimated to be much higher.
The mobilisation of hundreds of thousands of men took them off the job market, while prompting many of the most educated parts of the population to flee the country.
"Russia lacks workers," said Alexei Raksha, a demographer who previously worked at the Rosstat statistics agency.
"It's an old problem, but it has gotten worse due to mobilisation and mass departures," he said.
Russia inherited low birth rates with the collapse of the Soviet Union in the 1990s, when birth rates had halved due to economic hardship and uncertainties over the country's future.