An aid convoy on Tuesday passed through a newly re-opened border crossing into rebel-held north Syria, where help has been slow to arrive since last week's earthquake, which killed nearly 40,000 people in the region.
As hopes fade of finding people alive under the debris more than 200 hours after the 7.8-magnitude quake struck, the focus has switched to providing food and shelter to the vast numbers of survivors.
A caravan of 11 United Nations trucks entered Syria through the re-opened Bab al-Salama border point, after Damascus agreed to let the world body use the crossing for aid.
Before the earthquake struck, almost all the crucial humanitarian aid for the more than four million people living in rebel-controlled areas of northwest Syria was being delivered through just one crossing.
The trucks were loaded with essential humanitarian assistance, including shelter materials, mattresses, blankets and carpets, Paul Dillon, a spokesman for the UN's International Organization for Migration (IOM), told AFP.
A UN delegation also travelled from Turkey into the rebel-held area for the first time since the quake on an fact-finding mission.
Activists and emergency teams locally have decried the UN's slow response to the quake in rebel-held areas, contrasting it with the planeloads of humanitarian aid that have been delivered to government-controlled airports.
"I don't want to sit here and give excuses, but I wanted to share that we are all collectively in the same place," Sanjana Quazi, who heads the UN Office for the Coordination of Humanitarian Affairs in Turkey, told reporters in the rebel-held town of Sarmada.
The UN also launched an appeal for $397 million to cover three months of "life-saving relief" for victims in Syria and said it was close to a similar plan for Turkey.
"Millions of people across the region are struggling for survival, homeless and in freezing temperatures," UN Secretary-General Antonio Guterres said.
Fears have grown for survivors on both sides of the border, with the UN saying more than seven million children have been negatively impacted between Syria and Turkey, and noting fears that "many thousands" more had died.