| Twenty people were killed and 18 lorries destroyed in last Monday's attack |
The US ambassador to the UN has accused Russia of "barbarism" over the bombing of the Syrian city of Aleppo.
Russia said Syrian forces were trying to remove terrorists from Aleppo while harming as few citizens as possible. Ambassador Vitaly Churkin did not say Russian forces were involved.
But he said that bringing peace to Syria was "almost an impossible task now." He also accused opposition armed groups of sabotaging the ceasefire.
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One hospital told the charity that 43% of the injured they treated on Saturday were children, and a Syrian ambulance crew said more than 50% they picked up in the past 48 hours were children.
'New heights of horror'
Ms Power told the meeting that Russia, which is supporting the regime of Syrian President Bashar al-Assad, had "long had the power to stop this suffering". She said: "Instead of peace, Russia and Assad make war.Instead of getting life-saving aid to Syrians, Russia and Assad are bombing hospitals and first responders." She accused Russia of preparing air strikes against eastern Aleppo even at the very moment its Foreign Minister Sergei Lavrov was telling the UN that Russia was committed to a peaceful solution.
Ms Power went on to call on the council to "have the courage to say who is responsible and tell Russia with one voice to stop".
Several representatives at the meeting suggested Russia may have committed a war crime over the bombing of a humanitarian convoy near Aleppo on Monday.
Russia has denied carrying out the attack, which destroyed 18 of 31 aid trucks. It has said that rebel shelling or a US drone were responsible. Russia has not admitted to bombing Aleppo since the end of the recent ceasefire.