The Kremlin on Tuesday rejected a U.S. assessment of Russian military casualties in Ukraine as having been "plucked from thin air" and said that Washington had no way of obtaining the correct data.

The White House on Monday estimated that Russia's military had suffered 100,000 casualties in the last five months, including more than 20,000 dead.

Russia last publicly revealed its own tally of losses in the campaign in September, when Defence Minister Sergei Shoigu said 5,937 Russian soldiers had been killed in the conflict. (Reporting by Reuters Editing by Andrew Osborn)