Russian troop build-up threatens city seen as key to seizing Ukraine's Donbas

The recent troop build-up by Russian forces near Kostyantynivka signals a significant escalation in the conflict in Ukraine's Donbas region. If the city falls, Russian forces could advance toward the remaining Ukrainian strongholds in the east, potentially altering the course of the war. This development underscores the strategic importance of the Donbas region, which could become a focal point for further military operations and international diplomatic efforts to resolve the ongoing crisis.