"President Obama was clear that we intend to continue our efforts to degrade and ultimately destroy ISIL in Syria and to keep supporting the moderate Syrian opposition," the official said, using another name for ISIS.
While Russia has said that it is conducting military operations to wipe out ISIS, U.S. officials have questioned that aim given that many of its airstrikes have not targeted places ISIS is active. Instead, they have seen the effort mostly as a move to bolster close Moscow ally President Bashar al-Assad.
The latest U.S. assessment of Moscow's activity in western Syria indicates Russia has moved several ground combat weapons and troops into the area to potentially back up Syrian forces in the field planning to attack anti-regime forces, according to two U.S. defense officials.
The U.S. views the move as Russia "stepping up its ground activity" in Syria to attack those forces, rather than ISIS elements, according to one of the officials.
It's believed the Russians are positioning the weapons to be able to support a Syrian ground offensive, the officials said.
Obama authorizes resupply of Syrian opposition - CNNPolitics.com