The four-decade-old United Nations peacekeeping operation in the Golan Heights region between Israel and Syria, largely curtailed last week because of Syria’s civil war, was further undermined on Tuesday with confirmation that the Philippines contingent was going home.

President Benigno S. Aquino III of the Philippines said in an interview while attending the United Nations Climate Summit that most of the Filipino soldiers, having retreated from the buffer zone between Israel and Syria to the Israeli side last week because of Syrian insurgent attacks, had departed for the Philippines, with the rest to follow.

Mr. Aquino has grown increasingly exasperated with the Golan peacekeeping operation, known as the United Nations Disengagement Observer Force, or Undof, which is ill equipped to deal with heavily armed Syrian insurgents who have encroached with growing frequency.