President Barack Obama has called for an immediate, unimpeded investigation at the crash site of Malaysia Airlines Flight 17, which was shot down four days ago near the Ukrainian border.
Speaking on Monday at the White House, Obama expressed frustration at pro-Russian separatists for hampering an international investigation at the crash site to determine who was responsible for shooting down the plane. He said Russian President Vladimir Putin had a "direct responsibility" to use his influence with the rebels to stop hindering the probe.
"Separatists are removing evidence from the crash site," Obama said. "Which begs the question: What exactly are they trying to hide? The burden now is on Russia to insist that the separatists stop tampering with the evidence."
He also noted that Russian trained and armed the separatists which no one denies.
Obama said he appreciated Putin's comments supporting a full investigation, but he said it was now on Putin to act.
"President Putin has a direct responsibility to compel them to cooperate with the investigation," Obama said. "The world deserves to know exactly what happened."
If Putin doesn't comply and Russia continues to back the pro-Russian separatists in eastern Ukraine, Obama promised additional "costs."