A "credible" international investigation is needed into understanding what happened to a Malaysia Airlines passenger plane, President Obama told a conference.
Mr Obama told reporters that the deaths of 298 people were "an outrage or unspeakable proportions", adding that one US citizen is confirmed to have been on board the flight. He said it was important to avoid "misinformation" at this time.
Mr Obama accused pro-Russian separatists in eastern Ukraine had received a steady flow of support from Russia including obtaining heavy weapons and anti-aircraft weapons.
He added that Russia had refused to take steps necessary to de-escalate the situation the country, calling on all parties to adhere to an immediate ceasefire. The US president, however, said that he told Russia to solve the situation diplomatically.
Thousands of online users have taken to social media to call for the victims of the Malaysian airliner crash to be returned to loved ones.
United States intelligence officials admitted that they do not know who fired the surface-to-air missile that downed flight MH17.
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