Story highlights Obama warned that Russia's air campaign against Syria would only lead to further bloodshed and bog down Moscow

Obama's comments come after a scramble by his administration to respond to Russia's strikes

Washington (CNN) President Barack Obama said Friday that he was willing to work with Russian counterpart Vladimir Putin on moving Syria away from civil war, but only if that plan includes removing Syrian President Bashar al-Assad from power.

In the absence of that, he warned that Russia's air campaign against Syria would only lead to further bloodshed for the war-torn country and bog down Moscow.

Russia, he predicted during a White House press conference, would get stuck in a "quagmire," adding, "It just won't work, and they're going to stay there for a while."

Saying Syria's civil war doesn't directly involve the United States -- but instead pits Assad's forces against rebel groups -- Obama admitted elements of his strategy had failed. A plan to train and equip opposition forces, which resulted in only a handful of trainees, "did not work the way it was supposed to," Obama said.

But asked whether he now backs no-fly zones in Syria -- which his former secretary of state, Hillary Clinton, recommended this week during her presidential campaign -- he warned against "easy, low-cost answers" to ending the war.

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