WASHINGTON — The Pentagon's top official said Thursday that Turkey must "do more" to help in the fight against the Islamic State militant group, commonly known as ISIL or ISIS.

US Secretary of Defense Ash Carter called Turkey's participation in anti-ISIL operations "overdue." And while the decision by Turkey to help with the air campaign against the militant group is welcome, Carter specifically called out the need for Turkish forces to secure the border with Syria in order to stop the flow of supplies and ISIL operatives.

"We need them — also, as a neighbor to this conflict zone, as longtime NATO ally and a responsible member of the anti-ISIL coalition — to control the border, the long border that they have with both Syria and Iraq, more than it has been controlled over the last year," Carter said. "It is a border over which logistics for ISIL and fighters cross, and so we're looking for them to do more in that regard as well, and we're in active discussions with them in that regard."

For the last year, Turkey had avoided large-scale engagement with the militant group. However, after an ISIS suicide bomber killed 32 people on a Turkish town bordering Syria on July 20, the government of President Recep Tayyip Erdoğan decided to clear US airstrikes from inside its territory.

On Aug. 4, the US launched its first military strike from Incirlik Air Base, the first such strike conducted after Turkey gave the ok OK for the US to launch strikes from its territory. Since then, US forces have begun launching regular airstrikes, of both have launched manned and unmanned strikes systems, from the Turkish base.

The next step for Turkey, including participation in anti-ISIL strikes, is still being discussed, Carter said. But he waved away the idea that the government is moving slowly on working such agreements.

"I don't think they're dragging their feet — I think their leadership has indicated that this needs to be done," Carter said. "It's overdue because it's a year into the campaign, but they are indicating some considerable effort now, including allowing us to use their airfields. That important, but it's not enough."

With the war against ISIL reaching over surpassing a year and no clear end in sight, Carter denied that the fight is stuck in a "stalemate," instead saying he was "confident" the group can be defeated.

"It is hard work. It is difficult work," he acknowledged, before emphasizing the role of regional partners in the operations.

"I think we have the right strategy," he said. "We're getting Turkey more into the fight now. Iraq, obviously, was in no position to effectively counter ISIl last summer. It is in a better position this summer than last summer."

Twitter: @AaronMehta