President Obama said at least one American citizen had been killed in the Malaysia Airlines crash in Ukraine in a speech from the White House on Friday.
The U.S. State Department confirmed the citizen as Quinn Lucas Schansman, a dual national Dutch/American citizen.
The president also indicated that evidence points to the plane having been shot down by a surface-to-air missile from the separatist-controlled area of eastern Ukraine. He added that these separatists have received "a steady flow of support from Russia," including arms, training, heavy weapons, anti-aircraft weapons.
U.S. markets were unfazed by the speech, climbing slightly to new session highs. ( for the latest on the markets.)
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Obama emphasized that an immediate course of action must include a "credible international investigation" into the incident.
"We don't have time for propaganda, we don't have time for games, we need to know exactly what happened," he said.
He also placed some of the blame for the incident on Russia.
"Time and again Russia has refused to take the concrete steps necessary to deescalate the situation," Obama said. "I spoke to President Putin yesterday in the wake of additional sanctions that we'd imposed. He said he wasn't happy with them, and I told him that we have been very clear from the outset that we want Russia to take the path that would result in peace in Ukraine, but so far at least, Russia has failed to take that path."
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The president said he does not see a U.S. military role beyond what is currently being done in working with its partners in the region, and that any positive change in the region may require cooperation from Moscow.
"The violence that is taking place [in eastern Ukraine] is facilitated in part—in large part—because of Russian support, and they have the ability to move those separatists in a different direction," Obama said.
In response to a question about further U.S. and European sanctions against Russia, the president said that the incident "certainly will be a wake-up call for Europe and the world that there are consequences to an escalating conflict in Eastern Ukraine." He also discussed earlier sanctions, saying that a "relevant consideration" is to minimize their effect on America and the global economy.
Most experts who have spoken with CNBC concurred that the plane was likely downed by Russian separatists operating in Ukraine, but investigators have yet to definitely determine the origin of a missile.
U.S. officials told NBC that it is "absolutely" possible that the Russian military shot down Flight MH17, although the matter needs to be investigated further.
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"Because of the technical complexity of the SA-11 [missile system believed to have shot down the flight] it is unlikely that the separatists could effectively operate the system without assistance from knowledgeable personnel, thus we cannot rule out technical assistance from Russian personnel in operating the system,'' U.S. Ambassador to the United Nations Samantha Power told the U.N. Security Council on Friday.
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—By CNBC staff