CBS News reports: HANGZHOU, China — The U.S. and Russia are near completing a groundbreaking deal that involves military and intelligence cooperation to fight al Qaeda and ISIS-linked terrorists in Syria. That is in exchange for Russia agreeing to pressure Syrian dictator Bashar al- Assad to stop bombing civilians and allow in humanitarian aid to all starving areas.

The potential deal would ground Assad’s own air force to prevent it from continuing its bombing and chemical attacks on civilians and U.S.-backed rebels. In turn, food and medical aid deliveries will be allowed into besieged cities like Aleppo, where hundreds of thousands of civilians have been trapped due to the joint assaults by Syrian and Russian forces.

Syrian opposition sources tell CBS News that U.S. Envoy to Syria Michael Ratney has circulated a letter notifying their political leadership that the U.S. has reached an understanding with Russia. Having been burned by multiple failed attempts at brokering a successful deal with Russia, American diplomats caution that the diplomacy is in flux.

After many failed attempts at convincing Russia to abandon its support for Assad, this is a last-ditch effort by the Obama administration to stop the killing and the flow of refugees from Syria. An estimated 5 million Syrian refugees have fled the country during the past six years of war while more than 400,000 Syrians have been killed.

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