The Pentagon Monday leveled sharp criticism at a military offensive on northern Syria, which has displaced tens of thousands of Kurds, killed hundreds of civilians and is creating a humanitarian crisis, all while carefully not mentioning the country carrying out the offensive, Turkey.

“Civilian casualties, not getting humanitarian assistance, a growing humanitarian crisis. It’s gotta be stopped. It’s gotta be averted,” Col. Rob Manning, a Pentagon spokesman, told reporters.

Pressed by a reporter from the Turkish Anadolu News Service about who specifically was to blame for the worsening situation in the North, Manning refused to name Turkey, a NATO ally, and simply called on all sides to stop.

“More than who to blame, is the need to stop it, and the need to ensure that all parties focus on the reason why they are there,” which Manning said is to defeat Islamic State.

The U.S. has complained to Turkey that its two-months-old offensive, which captured the city of Afrin over the weekend, is siphoning off Kurdish fighters from the fight against ISIS in the east to battle Turkish and Syrian rebel troops in the west.

“We are very concerned about the effect that fighting there has had on our defeat ISIS efforts, and would like to see an end to the hostilities before ISIS has an opportunity to regroup in eastern Syria,” Manning said. “We cannot allow ISIS to regain momentum at this critical point.”

The U.S. has relied on heavy bombing of ISIS positions in the Middle Euphrates River Valley to keep the group from retaking any ground while the remaining Syrian fighters there have been relegated to reinforcing their defensive positions.

The Pentagon says the U.S. remains in talks with Turkey to try to find a solution that would address what it calls Turkey’s “legitimate security” concerns along its southern border, but would also halt the offensive that has effectively stalled the final push by U.S.-backed Kurdish and Arab forces to finish off ISIS.

“Further operations beyond the border regions will draw in more forces and further exacerbate an already deteriorating humanitarian situation,” Manning said. “We are concerned about reports indicating civilians are unable to access potable water. Clean water is vital to survival. We encourage all parties to allow the free flow of these resources and much-needed humanitarian aid throughout Syria.”

The U.N. office for humanitarian affairs said last week that after the Turkish army took control of a dam and a water pumping station northeast of Afrin, water was cut off to local residents, who have since relied on untreated water from wherever they can get it.

Turkish President Recep Tayyip Erdogan has vowed to clear a wide swath of northern Syria of any elements of the Kurdish YPG militia, who he considers terrorists, and to send his forces east toward Manbij, where a small number of U.S. troops is garrisoned along with U.S.-backed Kurdish forces.

The U.S. has not said if the U.S. troops would protect their Kurdish partners in Manbij should Turkish forces tried to enter the city, but the Pentagon notes that American troops always have the right to self-defense.

The State Department is engaged with Turkey to try to resolve “a number of shared security issues, one of which is Manbij,” a Pentagon spokesman said.