When Ukraine and Russia-backed rebels signed a ceasefire deal last month in Minsk, they agreed that Ukraine would regain control of the country's border with Russia.
Russia's War Against Ukraine
BBC: Ukraine prospects of peace; monitoring a ceasefire
Russian President Vladimir Putin (C) meets with Defense Minister Sergei Shoigu (L) and Chief of General Staff Valery Gerasimov (R) at the Kremlin on March 24, 2015.
