Story highlights President Barack Obama spoke at the end of a climate change conference in Paris

Because of recent terror attacks, the fight against ISIS was also a major point of discussion for world leaders

Obama warned his Russian counterpart against intervening in Syria's civil war

Paris (CNN) President Barack Obama warned his Russian counterpart Tuesday against intervening in Syria's civil war, suggesting that Vladimir Putin is aware of the dangers his country faces by entering the bloody conflict.

"I think Mr. Putin understands that ... with Afghanistan fresh in the memory, for him to simply get bogged down in an inconclusive and paralyzing civil conflict is not the outcome that he's looking for," Obama said at a news conference in Paris.

Obama said he does not disagree with Putin -- with whom he met on Monday -- on the necessity of a political resolution to Syria's conflict. But he said there remains discord over the fate of Syrian President Bashar al-Assad, who the United States insists must leave power as part of a political transition. But he said the reality on the ground in Syria could change Putin's calculus.

"I think it is possible over the next several months that we both see a shift in calculation in the Russians and a recognition that it's time to bring the civil war in Syria to a close," Obama said. "It's not going to be easy."

Obama said that he leaves the major climate change conference -- that united world leaders in one city -- with confidence in the forward trajectory of his ISIS strategy, which he said must include new efforts to stamp out financing for the terror network.

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