More than 100 U.N. trucks have delivered desperately needed food, medicine and other humanitarian relief to five Syrian towns under siege by Syrian forces or rebels.
Nearly 100,000 sick and starving men, women and children will now be fed and treated under an agreement between the Syrian government and the United Nations.
The trucks reached Moadimayet al-Sham, a rebel-held town near Damascus encircled by President Bashar al-Assad's forces.
Other vehicles reached Fuaa and Kafraya, two Shi'ite towns in northwestern Idlib province besieged by rebels, while U.N. trucks also entered Madaya and Zabadani, two other towns near Damascus under siege by Syrian forces.
The U.N. envoy for Syria, Staffan de Mistura, said Wednesday in Damascus that these deliveries would be a test of the government's commitment to allow the United Nations to bring humanitarian aid directly to people trapped by the war.
Syria's Foreign Ministry shot back at those comments, saying it did not need reminders about its responsibilities.
The United Nations has repeatedly called for all parties in the five-year-long Syrian conflict to allow unhindered humanitarian access.
U.N. officials estimate 13.5 million people still in Syria need humanitarian assistance. Another 4.6 million Syrians have fled the country as refugees since early 2011.