During a press conference on Sunday in Kuala Lumpur, Malaysia, U.S. President Barack Obama said Russian airstrikes appear to be aimed at opposition forces instead of DAESH.
"Russia needs to make a strategic decision to go after the ISIS [DAESH] group, not the moderate opposition forces trying to topple Syrian President Bashar Assad," Obama said, adding "Assad has to go."
"Nearly two dozen nations including Turkey have taken action against ISIS so far, we will ultimately destroy them," Obama said, emphasizing that the U.S. led coalition is determined to eradicate DAESH.
The almost five years of fighting between the Assad regime and rebels created a vacuum that has allowed DAESH to thrive in both Syria and Iraq. The terrorist group is now setting its sights on targets outside its stronghold, including the attacks in Paris that killed 130 people and wounded hundreds more.
The U.S. and its international partners would not relent in their fight against the terrorist organization, Obama said, insisting that the world would not accept attacks by extremists on civilians anywhere in the world.
The U.S. held firm to its calls for Assad's departure, with Obama insisting that the war could not end unless the Syrian leader steps down.
"I do not foresee a situation in which we can end the civil war in Syria while Assad remains in power," Obama said.
Top diplomats from 17 countries met in Vienna Saturday to discuss a way out of Syria's nearly five-year conflict, which has left more than a quarter of a million people dead.
They produced a two-year timetable: a transitional government would be formed and a new constitution written within six months, to be followed by internationally monitored elections within 18 months after that.
But in a recent television interview with Italy's Rai television, Assad said there could be no transition schedule for elections while swathes of Syria remained out of government control.
"This timetable starts after starting defeating terrorism. You cannot achieve anything politically while you have the terrorists taking over many areas in Syria," he said.
"If we talk after that, one year and a half to two years is enough for any transition."