On Monday, the White House reported that Russia has suffered 100,000 casualties, with over 20,000 deaths, since December as Ukrainian forces repel a heavy assault by Russian troops in eastern Ukraine.
The fiercest fighting has been in the eastern Donetsk region, where Russia is attempting to encircle Bakhmut amidst fierce resistance from Ukraine.
The United States derived the estimate based on newly declassified intelligence, although the specifics were not provided.
Chairman of the Joint Chiefs of Staff General Mark Milley had previously stated in November that Russia had suffered more than 100,000 casualties in the first eight months of the war, indicating that Russian losses have accelerated significantly in recent months.