The United Nations said Sunday it began delivering aid to hundreds of thousands of Syrians through the Jaber-Nassib border crossing with Jordan, which reopened two months ago.
In total, "369 trucks carrying 11,200 metric tons of... assistance for over 650,000 people" will be involved in the four-week operation, the UN's humanitarian agency OCHA said.
The "exceptional" delivery, which amounts to one-month's worth of aid, would be carried out by six UN agencies and one international NGO, it added.
"This is a major logistical operation in an effort to mitigate the suffering of the Syrian people," said Anders Pedersen, the UN humanitarian coordinator in Jordan.
Among the immediate needs of Syrians were food, shelter, water and medical care, according to OCHA.
"We are working closely with our UN partners inside Syria to ensure this assistance reaches those who need it most," Pedersen added.
Syrian regime forces retook control of the border crossing from rebels in July.
Known as Jaber on the Jordanian side and Nassib in Syria, the crossing is a key Middle East trade route and its reopening in October after a three-year closure was seen as a boon for the economies of both countries.
Syria's civil war has killed more than 360,000 people since it started with the brutal repression of anti-government protests in 2011.
More than half the country's 23 million people have fled, with 6.6 million of those internally displaced and more than 5.6 million going abroad, according to UN figures.