BEIRUT — Turkey and Russia are discussing the contours of a broader Syrian cease-fire after brokering the deal that evacuated rebel-held eastern Aleppo earlier month, Syrian opposition factions said Wednesday.

Several rebel groups say they are withholding their approval of any agreement until they receive more details.

An official with one of the factions told The Associated Press that Russian and Turkish officials were debating a cease-fire proposal that would encompass the whole of Syria. He spoke on condition of anonymity because the talks were ongoing.

Rebels have opposed previous proposals that would allow the government to continue its offensives around the outskirts of the capital, Damascus.

Turkey’s Anadolu Agency said Wednesday morning that Ankara and Moscow had reached an agreement, and Turkish media reports quoted Foreign Minister Mevlut Cavusoglu as saying that a lasting cease-fire and political solution in Syria are “close.” But no details were announced, and there was no confirmation from state officials.

The Syrian opposition official said factions were holding vigorous discussions over the possibilities. Another official with a different group said the proposal has not been formally presented to the opposition.

“It is difficult to accept or refuse the matter before we look at the details, of course,” said the official, who also spoke on the condition of anonymity so as not to prejudge intra-opposition talks.

Previous attempts at enforcing a nationwide cease-fire in Syria have failed, but the recent warming of ties between Russia and Turkey, who provide crucial support to opposing sides of the civil war, may prove to be a game changer.

The foreign ministers of Turkey, Russia and Iran met in Moscow last week for talks on Syria that pointedly included no Syrians, indicating they prefer to pursue a grand bargain among great powers rather than a domestic settlement between the government and the opposition.

The Anadolu report quoted unnamed officials as saying a plan for a cease-fire “in all regions” would be presented to the warring parties. The cease-fire would exclude terrorist organizations, it said, without elaborating on which groups would be left out.

It said peace talks in Kazakhstan would proceed under Russia and Turkey’s leadership if the cease-fire holds, with the two acting as “guarantors” of any deal.

Russian President Vladimir Putin’s spokesman confirmed Russia and Turkey were in “constant contact” to prepare for planned Syria peace talks in Kazakhstan, but did not comment about the possibility of a cease-fire.

Mosayyeb Naimi, a Tehran-based political analyst, said it was unclear whether Turkey could corral Syria’s fractured opposition.

“Turkey’s ability to convince armed groups to accept the cease-fire is unknown, particularly because Turkey is involved in conflict with some of those groups,” he said. Naimi added that although the Russians have made initial agreements with Ankara, they may be waiting for U.S. President-elect Donald Trump to take office to discuss the U.S. role in the cease-fire process.