President Obama calls the Malaysia Airlines jet crash a "global tragedy."
Obama says at least one American citizen was a passenger along with almost 300 innocent people killed when the jet was shot down over Ukraine.
Obama says America must be firm in her support of Ukraine and the efforts to de-escalate separatist conflict.
The death of over 100 Dutch citizens "sadly brings home the degree to which the stakes are high for Europe, not simply the Ukrainian people."He says the incident is a "wake-up call for Europe and the world that there are consequences for a conflict in Eastern Ukraine."
Evidence implies the plane was shot from the skies by a surface-to-air missile in a region under Russian-backed separatists' control, Obama said.
He added that pro-Russian separatists "are armed and heavily trained, we know that that's not an accident."
Obama says he does not want to "get ahead of the facts" and assign blame at this time.