France's President Francois Hollande today called for united international action to tackle the threat from the Islamic State militants as he opened a conference on Iraq that brings together some 40 nations, including 10 Arab states, in a US-led anti-ISIL coalition and have also offered military assistance.
Iran, the highly influential neighbour of Iraq, is not attending the conference.
Earlier, the United States outlined a plan to combat the Islamist militants simultaneously in Iraq and Syria.
The beheading of a third Westerner, a UK citizen this time, has fuelled anger and brought the UK firmly into the coalition.
After a ''successful'' Middle East trip to shore up support for the US plan against the Islamic State, secretary of state John Kerry told the conference he was ''encouraged'' by the military cooperation offered by the nations to fight the ISIL, as the Islamic State militants are still generally dubbed.
Around 10 Arab states have agreed to be a part of the US-led coalition, and have also offered military assistance.
The key highlight of Kerry's Mideast tour is said to be a communication signed in Jeddah by 10 Sunni Arab governments, who have wowed to contribute their share to fight the ISIL. These are Saudi Arabia, the United Arab Emirates, Egypt, Iraq, Jordan, Lebanon, Bahrain, Kuwait, Oman and Qatar.
Opening the Paris conference, Hollande said, ''The threat … is global, so the response must be global ... Iraq's fight against the terrorists is also our fight. We must commit ourselves together - that is the purpose of this conference."
Hollande had last week travelled to Baghdad to meet members of Iraq's new government.
Iraqi President Fuad Masum said he hoped the Paris meeting would bring a "quick response" to jihadists who have declared a caliphate or Islamic state ruled under Sharia law in the heart of the Middle East.
"Islamic State's doctrine is either you support us or kill us. It has committed massacres and genocidal crimes and ethnic purification," he told delegates.
Foreign ministers from the main European states, the five permanent members of the UN Security Council, Iraq's neighbours and the Gulf Arab states have gathered to discuss the political, security and humanitarian aspects of tackling Islamic State.
France has said it is ready to join US air strikes in Iraq but says legal and military limitations make it more difficult to participate in Syria, where Islamic State's main power-base lies.
Earlier, foreign minister Laurent Fabius said French aircraft would begin reconnaissance flights over Iraq today.
Norwegian foreign minister Boerge Brende has said that Oslo, which is at the Paris conference, was considering a military presence in Iraq.
"First and foremost we have said that there would an additional contribution to humanitarian work. But we are also considering whether we will, separately to the humanitarian help, also contribute with military capacity building," he said.