Censor.NET reports citing Independent.
Power accused Russia of "barbarism" and said the U.S. knew they had "consistently said one thing, and done the opposite" at the emergency session of the Security Council on Syria.
She said Security Council members must "have the courage to say who is responsible for this and in a single voice tell Russia to stop".
But she added the U.S. also believes it must do "everything in our power to find a way to halt the violence" and will "continue to look for any way possible to restore the cessation of hostilities."
In response, Russian envoy Vitaly Churkin accused the United States of lack desire to support the cease-fire.
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