With a precarious ceasefire holding in Syria for a second day, aid organisations geared up on Sunday to get desperately needed food and medicine to besieged residents.
An estimated 480,000 Syrians are trapped in the country and the United Nations said it expects the truce will allow 17 areas to immediately receive humanitarian assistance.
The truce agreement among most combatants in the Syrian war came into effect early on Saturday, aiming to halt fighting for two weeks and lead to peace talks in March.
The deal marks the biggest diplomatic push yet to end Syria's five-year war, which has killed more than 260,000 people and displaced millions from their homes.
 Russia halts air strikes as Syria truce takes hold
While scepticism abounds on whether it will hold, there is hope the ceasefire will allow humanitarian efforts to move forward.
"I am actually hopeful, which is a rare thing to say in the course of this conflict," Middle East analyst Hillary Mann Leverett told Al Jazeera.
"But to me the critically important point is this is the first time that the international community has actually tried a broad-based, almost nationwide ceasefire in Syria - it's been more than four years since this has been attempted.
"The very attempt to do so - the agreement to get this done - will at least pave the way in the interim period for aid to get to civilians in desperate need."
While some observers have expressed doubt about the truce holding, Leverett said the parties involved have stakes in seeing that it does. She said at the least it will give rebel groups time to re-arm, while government forces can consolidate their authority after recent territorial gains.  
"The incentives the parties have to stay a part of this ceasefire are important, they're real, and they're not something that will be easily reversed," said Leverett.   
The Syrian Observatory for Human Rights reported on Sunday, however, fighting was continuing in the north of Latakia province, with government forces shelling rebel-held villages in an ongoing offensive.
Twelve fighters were reportedly killed, said the UK-based group that relies on contacts throughout Syria for its information.  
President Bashar al-Assad's ally Russia said on Saturday it halted air strikes in Syria in accordance with the ceasefire brokered by Moscow and Washington.
Russia entered the Syrian conflict in September 2015 and its air power has played a significant role in the recent major gains by government forces.
At the Bab al-Salaama camp in northern Syria on the border with Turkey, thousands of tents are now home to internally displaced people.
"We left our homes because of Russian air strikes, they were non-stop and relentless. They didn't spare anybody," Mohammed Abu Ali told Al Jazeera's Jamal Elshayyal.
Ali and his pregnant wife slept in a car for a week in Aleppo before she gave birth and they fled the besieged city for the camp with their newborn.  
Before the ceasefire took hold, residents in the camp accused Russia of driving Sunni Muslims out of northern Syria with its air campaign. "They are targeting civilians, especially Sunnis," said Ali.
Abduljajwad Hafath, another camp resident who lost his left leg in an air strike, concurred. "The Russians are bombing our towns to empty them of the indigenous people," he said.