As Ukraine's leaders puzzle over how to cut off Russian support for a separatist rebellion in the east of the country, one of its richest men thinks he has the answer.
Billionaire businessman Ihor Kolomoisky has suggested building a wall along the almost 2,000-km (1,200-mile) land border with Russia to prevent fighters and weapons flooding in.
Kolomoisky has offered to stump up $136 million to fund the 2-meter-high, 25- to 30-cm-thick wall of reinforced steel, complete with electronic alarms, trenches and minefields.