Amid escalating tensions between the two Cold War-era rivals, the United Nations Security Council met late Saturday to resolve acrimony following the U.S.-led coalition air strikes earlier in the day which killed dozens of Syrian soldiers, jeopardizing a U.S.-Russian brokered ceasefire in the region-
The United States relayed its "regret" to the Russian government for what it described as the unintentional loss of life of Syrian forces in the strike, a senior Obama administration official said in an emailed statement. Still, U.S. ambassador to the United Nations, Samantha Power, used the opportunity to chastise Russia.
"Russia really needs to stop the cheap point scoring and the grandstanding and the stunts and focus on what matters, which is the implementation of something we negotiated in good faith with them," Power told reporters.
When asked if the incident spelled the end of the Syria deal between Moscow and Washington, Russia's U.N. Ambassador Vitaly Churkin said: "This is a very big question mark."
"I would be very interested to see how Washington is going to react. If what Ambassador Power has done today is any indication of their possible reaction then we are in serious trouble," Churkin told reporters.
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Moscow cited the strikes, which allowed Islamic State fighters to briefly overrun a Syrian army position near Deir al-Zor airport, as evidence that the United States was helping the jihadist militants.
"We are reaching a really terrifying conclusion for the whole world: That the White House is defending Islamic State. Now there can be no doubts about that," the RIA Novosti news agency quoted Russian Foreign Ministry spokeswoman Maria Zakharova as saying.
Power said Zakharova should be embarrassed by that claim. Churkin said Russia had no "specific evidence" of the United States colluding with Islamic State militants.
Zakharova said the strikes threatened to undermine the ceasefire in Syria brokered by Russia, which has been aiding Syria's President Bashar al-Assad in the civil war, and the United States, which has backed some rebel groups.
Australia also participated in the strikes and the Australian Department of Defence offered its condolences to the families of Syrian soldiers killed or wounded in the incident.
The ceasefire, which took effect on Monday, is the most significant peacemaking effort in Syria for months, but has been undermined by repeated accusations of violations on both sides and by a failure to bring humanitarian aid to besieged areas.
In its sixth year, the conflict has cost hundreds of thousands of lives, displaced half of Syria's pre-war population, prompted a refugee crisis in the Middle East and Europe and inspired a wave of terror attacks across the world.
Syria's army said the U.S.-led strikes, were "conclusive evidence" of U.S. support for Islamic State, calling them "dangerous and blatant aggression".
The incident also threatens to undermine proposed joint targeting by the United States and Russia of Islamic State and some other jihadist groups across Syria.
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