BEIRUT (Reuters) – Trucks carrying medical and food aid entered two blockaded towns near Damascus on Wednesday, meaning that humanitarian agencies have now reached all besieged areas of Syria this year, the United Nations said.

The 38-truck convoy carried aid for some 20,000 people the U.N. estimates are living in the rebel-held towns of Zamalka and Irbin, which are being besieged by the government side.

“Today is the first time we are able to move a joint convoy of the United Nations, the Red Cross and Syrian Red Crescent … to these two towns since November 2012, nearly four years ago,” the U.N. resident and humanitarian coordinator Yacoub El Hillo told reporters before the trucks headed in.

“It will mean that since the beginning of this year the U.N., the International Committee of the Red Cross and the Syrian Red Crescent have been able to reach all the besieged areas of Syria,” he added.

The ICRC said the aid included food parcels and wheat flour, hygiene kits and medicine.

The U.N. says there are more than half a million Syrians living in 18 areas across the country that are besieged by warring sides in the five-year conflict. Aid agencies reported deaths from starvation in government-besieged Madaya earlier this year.

Hillo said the delivery to Zamalka and Irbin would last about a month, and called for sieges to be lifted and regular aid access granted.

Aid agencies have repeatedly called for regular access to areas under siege, saying that one-off deliveries quickly run out and that those in need remain blockaded.

(Reporting by John Davison and Firas Makdesi in Damascus; Editing by Gareth Jones)