The United States said on Friday it was forming a “core coalition” to battle Islamic State militants, calling for broad support from allies and partners but ruling out committing ground forces.

President Barack Obama sought to use a NATO summit in Wales to enlist allied support in fighting the Islamist militants, but it is unclear how many nations might join the United States in air strikes in Iraq.

U.S. Secretary of State John Kerry and U.S. Defense Secretary Chuck Hagel told foreign and defense ministers from 10 nations on the sidelines of the summit on ways they can help. Kerry said, “We need to attack them in ways that prevent them from taking over territory, to bolster the Iraqi security forces and others in the region who are prepared to take them on, without committing troops of our own. Obviously I think that’s a red line for everybody here: no boots on the ground.”

Hagel said, “This group here this morning is the core coalition,.. It is the core group that will form the larger and extended coalition that’s going to be required to deal with this challenge.”  And nations involved include, The United States, Britain, France, Germany, Canada, Italy, Turkey, Australia, Poland and Denmark, whose Ministers have met to discuss a strategy for addressing the Sunni militant group.

Kerry also said he hoped the allies could develop a comprehensive plan fighting IS in time for this month’s annual U.N. General Assembly session in New York.