The unanimous UN Security Council vote backing action against Islamic State shows the world is united against the "evil death cult", British Prime Minister David Cameron said.
Israeli Prime Minister Benjamin Netanyahu called for "a global solution" to terrorism in a phone call with Francois Hollande on Wednesday to express his solidarity after the Paris attacks.
President Francois Hollande said France would step up the battle against the Islamic State (IS) group in Syria in the wake of Paris attacks he dubbed "acts of war".
CIA director John Brennan warned that the attacks in Paris were likely not a "one off event" and that he expects the Islamic State group has more operations in the pipeline.
Blasts shook the Islamic State group's Syrian stronghold Raqa as French air strikes hit weapons depots and a training camp in response to the attacks in Paris.
Up to 20,000 people, among them Prime Minister Lars Lokke Rasmussen, gathered for a candlelight vigil at the gates of the French embassy in Copenhagen mourn the victims of the Paris attacks.
The defense ministers of France and the United States agreed on "concrete steps" to intensify cooperation against the Islamic State group, the Pentagon said.
Multiple "terror" attacks in Paris increased the pressure on some 20 countries and organisations meeting in Vienna on Saturday to overcome deep divisions and help end Syria's horrific civil war.
Moscow called on Saturday for the international community to unite in its fight against terrorism after a string of attacks in Paris left more than 128 people dead on Friday.
The Paris attacks show it is more vital than ever to coordinate global efforts to fight terrorism, France's foreign minister said, vowing that French "international action" will not stop.
British Prime Minister David Cameron said he was "shocked" after at least 18 people were reported killed in multiple attacks in Paris, including one near the Stade de France sports stadium.
Sirens blaring, blood on the roads, weeping relatives: nightmare scenes played out on the streets of Paris on Friday night as at least 120 people were killed in simultaneous attacks.
Syria needs to eradicate "terrorism" to find a political solution to end the country's war, embattled President Bashar al-Assad told a visiting Russian delegation.
They gather in the dark, wave German flags and vent their fury at foreigners they fear are overrunning their homeland -- next week Germany's anti-Islamic PEGIDA movement turns one year old.
The Syrian crisis can only be solved through peaceful ways, Kazakhstan’s Foreign Affairs Minister Yerlan Idrissov said at the General Policy Debates at the UN headquarters in New York.
Students at a US college in Oregon where 10 people were killed by a lone gunman described scenes of panic and terror as they ran for their lives or hid in classrooms.