The White House on Tuesday accused Russia of engaging in a cover-up of the chemical weapons attack by Syrian forces that killed civilians and prompted American airstrikes.

The White House said that the US intelligence and numerous contemporaneous reports confirmed that the Syrians used sarin gas on their own people, New York Times reported.

The White House asserted that the Syrian and Russian governments have sought to confuse the world community about the assault through disinformation and "false narratives."

Senior White House officials, speaking on the condition of anonymity to discuss the government's view, said they could not comment on the possibility that the Russian government knew in advance of Syria's plan to carry out the chemical weapons attack, or of a subsequent attack on a hospital that was treating victims.

But one official said that, given the history of close cooperation between the Syrian and Russian militaries, Moscow must answer for the attacks.