US authorities estimate that 20 thousand Russian soldiers have been killed in Ukraine over the past five months. The assessment comes as Kiyv gears up to launch its spring counter-offensive. The US intelligence community hasn't detailed how it derived the figure, but says the battle for Bakhmut in the east has seen the highest number of casualties and is in line with some of the fiercest periods of fighting during World War II. FRANCE 24's Yinka Oyetade tells us more.