BREAKING: Syrian Government Announces Truce Backed by Russia and Turkey.

The announcement follows the retaking of all of Aleppo, once Syria’s industrial capital and a stronghold of the opposition, by forces loyal to President Bashar al-Assad, and negotiations in Moscow that involved Mr. Assad’s government, Russia, Iran and Turkey — but, pointedly, not the United States.

Not included in the agreement is the Islamic State, which controls territory in eastern Syria and across the border with Iraq; the Syrian affiliate of Al Qaeda, which is strongest in the country’s northwest; and “groups linked to them.”

It was not clear which of the scores of rebel groups scattered across Syria had agreed to the cease-fire, nor whether those that had not been consulted would abide by it. Throughout the war, rebel forces have failed to form a united leadership, and infighting among groups has been common.

It was also unclear what criteria the Syrian military and its Russian allies would use to define groups “linked” to the jihadists. In the past, they have dismissed much of the armed opposition as “terrorists” who could not be distinguished from jihadist groups.

The fighting ain’t over yet.