Ukrainian President Petro Poroshenko said on August 18 he did not rule out introducing martial law and a new wave of military mobilisation if the conflict with pro-Russian separatists worsened.
Poroshenko made his comments as fresh tension with Russia over Crimea reignited fears that a fragile ceasefire deal hammered out in the Belarusian capital Minsk in February 2015 could collapse following the deadliest month of fighting in a year.