Ukraine’s fortress city is surrounded: Russian troops have reportedly seized a key strategic city along the frontline. From the importance of dramatic drone warfare to Volodymyr Zelenskyy’s strategy of putting pressure on Crimea, Sky’s military analyst Sean Bell examines whether Russian President Vladimir Putin is about to make a key breakthrough. Could Moscow open the door to its biggest prize yet? The final capture of the Donbas. SUBSCRIBE to our YouTube channel for more videos: http://www.