The United States has no agenda except for getting to the truth of shooting down of the Malaysia Airlines Flight MH17, allegedly by the Russia-backed Ukrainian separatist, the White House has said.

"The (US) President's priority is that this investigation should be conducted by an international set of investigators that don't have an agenda beyond getting to the truth," White House Press Secretary Josh Earnest told reporters.

His remarks came as the Obama Administration intensified its international effort for an independent and impartial investigation into the shooting down of the Malaysian plane that killed all the 298 people on board.

The Boeing 777 was on a scheduled flight from Amsterdam to Kuala Lumpur when it was shot down over pro-Russia rebels-held territory of the eastern Ukraine on Thursday. It is still not clear if the Malaysia Airlines Flight MH17 was shot down purposely or mistakenly.