Barack Obama has told his Russian counterpart Vladimir Putin that he must recognise the new Ukrainian President, Petro Poroshenko in order to help de-escalate the crisis in eastern Ukraine.
According to a White House official, the US President also told Mr Putin that if Russia works with the new Ukrainian authorities there could be "openings" to reduce tensions in the region.
Deputy national security adviser Ben Rhodes added that Mr Obama had demanded "ceasing support for separatists in eastern Ukraine, and stopping the provision of arms and material across the border".
More top news
Windy and wet weather to end the month of May
They made it across a deadly sea this year, but their journey to what they hope will be political asylum had only just begun.
Scientists used modern forensic techniques to review the 'cold case' and determine the victim was probably killed by two blows to the head.