In the days after armed terrorists linked with the Islamic State group killed 130 people in and around Paris in November, U.S. and French officials in Washington formed what they call the Lafayette Group: A joint team that reviews how the two countries share intelligence, and how that effort can be improved.

The group, which shares its name with the French general who fought alongside American colonists during the Revolutionary War, includes Brig. Gen. Vincent Cousin, the French defense attaché in Washington, U.S. Undersecretary of Defense for Intelligence Marcel Lettre, and members of Defense Secretary Ashton B. Carter’s policy staff. The team, which has met twice so far, gives the French a way to make Carter aware of problems quickly, said a senior U.S. defense official, speaking on condition of anonymity to discuss policy issues.

The group’s formation underscores how the U.S. and French have expanded their relationship as the U.S.-led coalition against the Islamic State prepares for an expansion of the war. On Tuesday, Carter will embark on a multi-day trip to Europe that includes meetings in Paris with defense ministers from the countries providing some of the most significant contributions to the military campaign: France, Australia, Germany, Italy, the Netherlands and Britain.

Notably, no Arab nation will have representation at the meetings–a choice that highlights how the contributions of countries like Jordan and the United Arab Emirates to the military campaign have dwindled since the United States first began dropping bombs on militant targets in Iraq in August 2014 and in Syria a month later.

But Carter’s trip this week to Paris — his first since becoming defense secretary last year — also represents a desire to get the nations with “the most skin in the game together” to discuss operations and what is coming next, the senior defense official said.

“We very much want the Gulf states involved, and we want them to up their participation,” the official said. “There’s a lot of ways that we are talking to them about doing that, but until and unless that happens, I don’t think it’s appropriate that they come to a group… just because they’re Arab and I don’t think they would want to be there just because they’re Arab.”

In a speech last week, Carter laid out a plan for a broader war against the Islamic State this year that includes targeting the Iraqi city of Mosul and Syrian city of Raqqa, the militant group’s de facto capitals, addressing the spread of the Islamic State to other parts of the world, and protecting the United States against it at home.

Part of that is the introduction of a new elite expeditionary targeting force that has arrived in Iraq to fight the militants, he said. But he added that the nations whose leaders will attend the meetings in Paris this week may have more to offer in the fight.

“Each of these nations has a significant stake in completing the destruction of this evil organization, and we must include all of the capabilities they can bring to the field,” Carter said. “And I will not hesitate to engage and challenge current and prospective members of the coalition as we go forward.”

The senior defense official describing Carter’s trip this week said there are certain “niche capabilities” the other countries may be able to bolster, including the collection of intelligence, surveillance and reconnaissance. The successful Iraqi military campaign to take back the city of Ramadi, backed by the coalition, also highlighted that there are specific areas where more training would be helpful, including in the countering of improvised explosive devices, which riddled the city.

“This enemy likes to combine military tactics of a traditional army with an irregular warfare flavor,” the defense official said. “So they’ll build a berm and they’ll put an IED in it or they’ll rig a house with improvised explosive devices. So you need equipment plus correct training to handle that kind of a threat.”

From Paris, Carter is expected to fly to Switzerland to take part in the World Economic Forum in the mountain resort town of Davos. A variety of world leaders are expected to be there, including Afghan President Ashraf Ghani and Iraqi Prime Minister Haider al-Abadi.