President Obama is expected to speak about the situation in Ukraine today following the Malaysia Airlines MH17 crash.
Obama has said little over the situation so far, apart from a few words yesterday when he said the incident "looks like it may be a terrible tragedy".
However, it is now widely believed the plane was shot down and the White House has since put out a statement calling for a "full, credible and unimpeded international investigation".
Flight paths over Eastern Ukraine have been closed until further notice following the crash yesterday, when Flight MH17 from Amsterdam to Kuala Lumpur disappeared from the radar.
All 298 passengers died.
The majority of passengers were Dutch, with the Netherlands losing 189 nationals. There were also 27 Australians, 44 Malaysians, 12 Indonesians, nine British, four Germans, four Belgians, three from the Philippines, one Canadian and one New Zealander confirmed as among the dead.
It has not yet been confirmed whether there have been any US casualties.
Malaysia Airlines said the flight route had been declared safe by the Civil Aviation Organization.
"International Air Transportation Association has stated that the airspace the aircraft was traversing was not subject to restrictions," it said in a statement.
There were four other aircraft flying in the same area at the time of crash, but all continued their journeys safely.
Several airlines including Malaysia Airlines, Air France, Delta, Lufthansa and Wizz Air said they would now avoid Ukraine airspace.
British Airways said its flights were not using Ukrainian airspace, with the exception of its daily service between Heathrow and Kiev.
"We are keeping those services under review, but Kiev is several hundred kilometres from the incident site," it said. "The safety and security of our customers is always our top priority."
