An international aid convoy delivered desperately needed food aid to the opposition-held, war devastated Damascus suburb of Daraya for the first time in nearly four years, but opposition activists said distribution of the aid was held up amid heavy bombardment from the air by government forces Friday.

The suburb of Daraya, just southwest of the Syrian capital, has been under siege by government forces since November 2012 and has witnessed some of the worst bombardment during the country's civil war, now in its sixth year. Severe cases of malnutrition have been reported among its few thousand residents due to severe shortages of food and medicine.

The delivery of food supplies late on Thursday night by the Syrian Arab Red Crescent and the United Nations came hours after the UN said the Syrian government had approved access to 15 of the 19 besieged areas within Syria.

Last week, a joint convoy of the UN, the International Committee of the Red Cross and SARC reached Daraya and delivered medicines, vaccines, baby formula, and "nutritional items for children"— but no food.

The UN estimates that there are currently 592,700 people living under siege in Syria, with the vast majority of them — some 452,700 people — besieged by government forces.

Lifting the siege on rebel-held areas was a key demand by the opposition during indirect peace talks held in Geneva earlier this year.

SARC said the food delivery was coordinated with the United Nations in the Syrian capital. It said food, flour and medical supplies were delivered.

An opposition activist in Daraya said the government allowed minimal amounts of food stuff into the suburb in order to create problems between the starving residents.

"Nothing has been distributed so far and the barrel bombs are falling on the city," said media activist Muhannad Abu al-Zein. "They allowed in food stuff for a quarter of the families here."

The UN estimates that 4,000 to 8,000 people live in Daraya, which has been subject to a crippling government blockade since residents expelled security forces in the early stages of the 2011 uprising against President Bashar Assad.

The Britain-based Syrian Observatory for Human Rights, which closely monitors the fighting, also reported airstrikes on Daraya Friday.

An official with the UN's World Food Programme said in a video posted online by media activists in Daraya that WFP is delivering assistance to the suburb for the first time since 2012. He said that WFP had delivered about 480 food rations that would feed about 2,400 individuals for one month.

The WFP official said he had met with some beneficiaries of the food aid and community leaders. "The supply of the very basic commodities is very challenging, so as a consequence the prices of the commodities themselves are very high whenever they are available," he said.

"As a result most families are having to do with one meal, which is not complete as a meal, per day in order to be able to get by," he said.

An amateur video posted online showed UN SUVs and white SARC trucks driving through sand barriers in the dark until they were met by opposition fighters.

The video appeared genuine and corresponded to other AP reporting of the events.

Photographs posted online by activists in the suburb showed UN and SARC officials meeting local dignitaries and men removing WFP boxes from a white truck.

Among those joining the convoy into Daraya were the UN humanitarian coordinator for Syria, Yacoub El Hillo, and Khawla Mattar, a spokeswoman for the UN Special Envoy to Syria, Staffan de Mistura, according to photographs posted by local activists.