The Obama Administration moved closer to a military strike on Syria, sending Secretary of State John Kerry before the cameras to provide the justification of whatever form that assault will take.

Calling it a “moral obscenity”, Kerry left no doubt that the US blames Syria’s Bashar al-Assad regime for a chemical attack on a rebel-held area of Damascus’ eastern suburbs that killed at least 355 of the 3,600 people it sickened.

“Let me be clear. The indiscriminate slaughter of civilians, the killing of women and children and innocent bystanders by chemical weapons is a moral obscenity. By any standard, it is inexcusable. And despite the excuses and equivocations that some have manufactured, it is undeniable,” Kerry said.

The Secretary also sought to counter criticism from Assad’s allies in Moscow, saying that “anyone who could claim that an attack of this staggering scale could be contrived or fabricated needs to check their conscience and their own moral compass.”

Earlier, Russian Foreign Minister Sergei Lavrov said, “The use of force without the approval of the United Nations Security Council is a very grave violation of international law,” that he said would “sharply aggravate” the situation.