At least two trucks carrying food baskets and baby formula entered the northwestern villages of Foua and Kfarya, where 20,000 people are besieged by insurgents, the UK-based Syrian Observatory for Human Rights said.

Other trucks entered the Damascus suburbs Madaya and Zabadani where 40,000 people are besieged by government forces and Lebanese Hezbollah fighters.

The government-controlled Syrian Central Military Media released a video showing a convoy of SUVs from the ICRC and the Syrian Arab Red Crescent escorting at least two trucks into Madaya.

Not a single inter-agency convoy had been able to deliver in the last month, of the 20 that had been requested, Kevin Kennedy, UN regional humanitarian coordinator for the Syrian crisis, said on Tuesday.

Dozens of trucks had been expected to enter the besieged areas, but it was not immediately clear if all made it in. Previous planned deliveries have been canceled at the last minute or halted because of fighting.

The UN embarked on a plan in early 2016 to establish regular humanitarian access, but it was stymied by the government as well as an agreement between the warring parties to limit assistance to 60,000 of the most distressed, divided among the four towns.

Willful neglect?

Physicians for Human Rights issued a report earlier in Tuesday accusing the Syrian government of willfully denying international shipments of food and medicine to many Syrians in besieged areas.

The UN's Independent International Commission of Inquiry on Syria said government forces and their allies had shown a "complete disregard for civilian life and international law" through continued use of cluster munitions, incendiary weapons and chlorine gas.

The Syrian government and its ally Russia maintain they are fighting terrorism.

jbh/bw (AP, Reuters)