As reported by Censor.NET, Brennan said in an interview to BBC.
According to him, Russia continued to hold the key to Syria's future, but he expressed skepticism about its willingness to come to any kind of deal.
"I think President Trump and the new administration need to be wary of Russian promises," Brennan told BBC, arguing Moscow had failed to deliver in the past.
The administration of President Barack Obama has pursued a policy of backing moderate rebels fighting the Assad regime in Syria. The CIA director said that he believed the U.S. needed to continue that support to help rebels withstand what he called an "onslaught" carried out by Syria, Iran, Hezbollah and Russia.
As reported, the Syrian government aviation and Russia's warplanes have carried out new strikes on residential areas of Aleppo Nov. 27, killing 46 people and wounding 325.
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