Russian forces are closing in on the Ukrainian capital Kyiv as they fiercely blast their way through with overwhelming firepower amid mounting casualties and refugee crisis.

President Volodymyr Zelensky remains holed up in the capital. The West has reacted with economic warfare.

Meanwhile, former United States president Barack Obama says Russia’s brazen invasion of Ukraine and subsequent fierce attack on its people violates international law and basic principles of human decency.

Here is his statement on what it means, and what should happen next.