Some 23 countries that are part of the US-led coalition against Islamic State are meeting in Rome to review progress in Syria and Iraq, and amid concerns that a third battlefront may open soon in Libya.
The radical Islamist group has made inroads in the north African country. Last week, Italian Defence Minister Roberta Pinotti said her country was preparing militarily to counter that threat together with the United States, France and Britain.
"We are going to degrade and destroy Daesh and we need to do it faster," US Secretary of State John Kerry said at the start of the conference, using an Arabic acronym for the terrorist group.
German Foreign Minister Frank-Walter Steinmeier said there were already first signs of success against Islamic State in Iraq, where 25 per cent of territory lost to the extremist militia has been retaken and many cities have been liberated.
"It is important not only to celebrate the military victories but also to stabilize the liberated territories," he said in Rome.
Steinmeier will travel to Iran and Saudi Arabia after the meeting, and called on the regional rivals to play their part in resolving the conflict in Syria, saying they had a responsibility beyond their own borders.
Ahead of the Rome conference, Kerry held talks on Libya with his Italian and Qatari counterparts, Paolo Gentiloni and Hamad al Thani, as well as UN envoy Martin Kobler, the US State Department said.
They discussed "how the international community could further support Libyan efforts to move forward" with a national unity government, and urged the country's two rival administrations to agree to a joint list of ministers ahead of a February 8 parliament vote.