Fikret Bila, a columnist for the newspaper Milliyet, said in a television discussion that the Syrian ban on air movements, which he said he had learned of from military sources, meant that there was now an effective buffer zone, “at least from the perspective of airspace."

Two days of Turkish artillery barrages also provided important relief for the rebels, destroying a base the Syrian military had established near the town of Tal al Abyad after rebels captured the Syrian side of the Akcakale border crossing several weeks ago.

The skirmishing along the border between Syrian forces loyal to and opposed to Assad was not the only potential flashpoint in Turkish-Syrian relations.

In a step that Turkey might find threatening, Assad reportedly has allowed a Kurdish political faction in northern Syria to establish a combat battalion in Qamishli, the biggest predominantly Kurdish city in northern Syria. The decision would place Qamishli under the control of the military wing of the Kurdish Democratic Union Party of Syria, known by its Kurdish initials as the PYD. The PYD is closely linked with the PKK, or Kurdistan Workers Party, which has fought a guerrilla war for decades to establish an independent Kurdish state in southern Turkey and has killed dozens of Turkish civilians and soldiers in recent months as it undertook a new offensive.

The development was reported by the Kurdish Firat News Agency, which reports in Turkish.

Mona Yacoubian of the Stimson Center, a Washington think tank, said the Kurdish dimension of the Syrian uprising “is going to gain in prominence” as Assad’s military loses control of territory. She said the assertion of control by Kurdish nationalists tied to the PKK, if it leads to more attacks against Turkish targets, would cross a Turkish “red line.”

With Erdogan’s new war powers, Turkey will “feel compelled to respond,” she said.

McClatchy special correspondent Joel Thomas contributed from Istanbul.