Refugees are flowing out of Syria, fleeing the conflict.
More than 100,000 fled last month, the United Nations reported.
The world body has launched a new peace initiative that is given little chance of success.
More than 40 percent of the 234,000 refugees who have sought U.N. support have left in the last two weeks, the New York Times reported.
Tens of thousands more have escaped into the four neighboring countries that border Syria. Some 2.5 million Syrians desperately need help inside their country; more than 1.2 million are displaced inside Syria, the United Nations reported.
The humanitarian disaster is grave and deteriorating, U.N. Secretary General Ban Ki-moon told the General Assembly earlier this week. The conflict took a particularly brutal turn in August, he said.
The U.N. leader said: The continuing militarization of the conflict is deeply tragic and highly dangerous. He has asked the international community to help end the violence and assist civilians fleeing the fighting.
In recent weeks, air power unleashed by the Syrian government forces has slowed rebel advances but also endangered civilians. Iran has been accused of supplying weapons and other support to the government of President Bashar Assad.
Rebel leaders have said that Syrian government forces control the skies only, not the ground.
The United Nations and Red Cross have asked Syria to allow more access for humanitarian groups to help civilians.
But both sides refuse to compromise. The international community is split, with America and Europe supporting the rebels and Russia, Iran and China backing the Syrian regime.
Countless Syrian civilians have fallen in the 18-month struggle. Many more will die if the conflict is allowed to run its course. The international community has failed to stop this human tragedy.