GAZIANTEP, Turkey — Syrian opposition groups cautiously welcomed a truce deal Friday aimed at halting the bloodshed in Syria, but raised worries that it leaves room for Russia to continue a bombing campaign to aid Syria’s government.
The international agreement announced in Munich — backed by the United States, Russia and others — calls for a “temporary cessation” of hostilities to begin in a week.
It also calls for the delivery of humanitarian aid to besieged communities on both sides of the conflict and the resumption of stalled peace talks in Geneva later this month.
The deal marks the first attempt to bring about any kind of truce since a U.N.-backed cease-fire in 2012 collapsed hours after it went into effect.
Hundreds of thousands of people have subsequently died, more than half of Syria’s pre-war population has been displaced, a quarter have fled the country, and the Islamic State has emerged to present a global threat, adding new urgency to the quest for a solution to the region’s bloodiest war.
Russia’s military intervention last year, meanwhile, has tilted the balance of power on the ground in favor of President Bashar al-Assad, leaving the government with little incentive to compromise with rebels who no longer present a significant challenge to his hold on power.
Russian warplanes resumed their bombardment of rebel positions across Syria within hours of the deal, striking areas in the countryside around the northern city of Aleppo in support of a 10-day-old government offensive to lay siege to the city.
In Brussels, Russian Foreign Minister Sergei Lavrov told reporters that Moscow would continue its attacks against groups including the Islamic State.
The Russians have repeatedly said that they consider a number of Islamist groups fighting within the opposition to be “terrorist,” and have used this formulation to justify air attacks that have largely targeted the anti-Assad opposition.
Under the agreement, the United States and Russia will chair a task force to adjudicate questions about where and when bombing is permitted. But it remains unclear how those decisions will be made.
In Syria, residents of the areas of northern Aleppo have born the brunt of the recent bombing campaign. Many expressed dismay that the cease-fire would not come into effect for a week.
“Within a week everything will have been destroyed,” said Mohammed Najjar, a resident of the town of Marae, who on Friday joined an exodus of tens of thousands of civilians toward the Turkish border because the bombing had become too intense.
Details of how the truce would be implemented remain to be worked out, and the deal is subject to the approval of the factions on the ground, who were not party to the final accord reached by Russia, the United States and the European and Middle Eastern powers belonging to the International Syria Support Group.
Syrian rebels also questioned how the international community would enforce the truce, given that Russian warplanes will be allowed to continue bombing the terrorist groups Islamic State and Jabhat al-Nusra.
“The Russians target moderate groups and say we are Daesh,” said Lt. Col. Ahmed Saoud, the leader of the U.S.-backed Division 13 group, using the Arabic acronym for the Islamic State.
He described how one of his group’s bases in the northwestern province of Idlib was destroyed in a bombing raid last October that Russian military officials announced as a strike on an Islamic State base.
“I hope it will succeed,” he said of the agreement. “I wish for anything that will stop the bloodshed. We want a cease-fire and a political solution, but not just any cease-fire. We need international monitoring.”
Analysts were also skeptical that this agreement would end the bloodshed where so many other attempts have failed.
“It is an agreement full of holes and ambiguities,” said Emile Hokayem of the International Institute for Strategic Studies, who also noted the absence of monitoring mechanisms.
“This is an agreement struck because of an emergency, but it lacks any real political dimension,” he said.
The recent escalation of Russia’s air campaign has only deepened rebel suspicions of Russia’s intentions, said Issam Rayess, a spokesman for the U.S.-backed Southern Front opposition faction.
“Even now they continue to indiscriminately bomb civilians and our moderate groups into the dust, and they say they are hitting terrorists,” he said. “We no longer trust words. There have been too many recently, matched with opposite action on the ground from the Russians.”
The Syrian opposition’s High Negotiating Commission, formed to participate in the Geneva peace process, cautiously welcomed the deal but said the opposition wanted to see evidence of its implementation before agreeing to join any further peace talks.
“We must see action on the ground, and if we see action and implementation, we will see you soon in Geneva,” said Salem al-Meslat, the commission’s spokesman.
Mohammed Adib, a political officer with Jabhat Shamiya, the biggest rebel grouping in Aleppo, said rebel groups would meet in the coming days to decide whether to accept the deal.
“Most probably we will support it because we want a peaceful solution to the crisis,” he said.
After the scale of their setbacks in recent weeks, the rebels also recognize they have no choice, said Saoud.
“We are the weakest part of this chain, and we don’t have any cards,” he said. “If the Americans and the Russians agreed, then we will obey. We can only listen to their orders.”
There was no immediate response from the Syrian government, which has consistently made it clear that it regards all the groups fighting Assad as terrorists, not just the extremist Islamic State and Jabhat al-Nusra groups internationally designated as such.
International aid groups greeted the cease-fire plan with a mix of hope and caution.
“We wait with eager anticipation to see whether this agreement is a turning point or a false dawn,” said David Miliband, a former British foreign minister who heads the International Rescue Committee.
Neal Keny-Guyer, chief executive officer of the aid group Mercy Corps, wondered why the pact did not seek an immediate halt to the fighting, raising the risks for further suffering and humanitarian needs.
“We must ask,” said Keny-Guyer, “why wait one more week before the fighting stops?
Karen DeYoung in Brussels and Brian Murphy in Washington contibuted to this report.