Ten days of intense diplomatic maneuvers by Europeans and the US ahead of the meeting in Turkey were insufficient to reach a deal, as the differences between the two belligerent parties appear insurmountable.

ISTANBUL (Reuters) -Russian and Ukrainian negotiators were in Istanbul on Friday for what was billed as their first direct peace talks in more than three years, under pressure from U.S. President Donald Trump to end Europe's deadliest conflict since World War Two.