(CNN) -- Even as they trade barbs publicly -- and even as artillery shells and accusations continue to fly in Syria -- the United States and Russia could take solace Friday in at least one respect: They are still talking. Discussions between the two in Geneva -- centered around Moscow's proposal to have Syrian President Bashar al-Assad's government hand over its chemical weapons stockpile -- were supposed to end Friday. They continued through the night and were extended into Saturday for a reason, U.S. officials said. "If there was no opening, we wouldn't still be here," a senior State Department official said.
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NEW: U.N.-Arab League calls the Kerry, Lavrov talks "extremely important"
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NEW: A Russian spokesman says U.S. is "unaccustomed" to competition
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Official: Two sides are "closer to agreement" on scope of Syria's chemical weapons
Russia has stood by its longtime ally @placeholder, challenging the validity of the U.S. claims.
At the same time, and as the threat of @placeholder-led strikes loomed, Moscow raised its proposal on Syria's chemical weapons stockpiles and working through the U.N. -- this after, time and again, blocking U.N. action involving Syria.