Updated February 28, 2018 01:44:59

Fighting has continued in the Eastern Ghouta district of Syria, the United Nations says, despite a five-hour ceasefire called by President Bashar al-Assad's ally Russia.

"We have reports this morning there is continuous fighting in Eastern Ghouta," UN humanitarian spokesman Jens Laerke told a briefing in Geneva.

"Clearly the situation on the ground is not such that convoys can go in or medical evacuations can go out."

The Britain-based monitoring group the Syrian Observatory for Human Rights said helicopters dropped two bombs on one town in the east Ghouta enclave and a warplane struck another town during the truce.

Eastern Ghouta had initially been mostly calm after the ceasefire took effect at 9:00am (local time), the Observatory and residents said, though state television reported that insurgents had shelled an evacuation route.

A Syrian military source denied there had been air strikes.

Reuters was not immediately able to verify either report.

A UN Security Council resolution calling for a 30-day nation-wide ceasefire was unanimously voted in Saturday, a rarity in the diverse Syria crisis that has morphed into a proxy war drawing in nations across the globe.

Joelle Bassoul, regional communications director for CARE, told the ABC that the terms of the UN ceasefire were now being dictated by Russia.

She said there were high hopes initially for the ceasefire, but it has not been fully implemented.

"We went from a 30-day full ceasefire to just five hours per day announced by Russia," she said. "And today it looks like they haven't even respected the full five hours."

The UN resolution excludes some militant groups which Damascus says its forces have been battling in Eastern Ghouta.

More than 500 people have died during 10 days of government bombardment of Eastern Ghouta, a rebel-held area of towns and farms on the outskirts of Damascus.

The assault has been among the most devastating air campaigns of a war now entering its eighth year.

Photo: Regime warplanes continue to pound eastern Ghouta, with more civilians killed. (Reuters: Bassam Khabieh)

"It is a question [of] life and death — if ever there was a question of life and death — we need a 30-day cessation of hostilities in Syria as the Security Council demands," said Mr Laerke, spokesman of the UN Office for the Coordination of Humanitarian Assistance (OCHA).

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Russia had called Tuesday's five-hour truce in the enclave to allow a safe route for wounded to be evacuated and civilians to escape.

Ms Bassoul said the humanitarian situation was dire with civilians lacking food and medical supplies in one of the "worst situations" seen in Syria for years.

"If the ceasefire is not respected … we are going to see people pushed into a situation where more deaths will occur, not just from airstrikes but from the lack of food and nutrition," she said.

Moscow and Damascus accuse rebels of attacking this humanitarian corridor to prevent civilians from leaving. Rebels deny this.

Eastern Ghouta, where the UN says about 400,000 people live, is a major target for Assad, whose forces have clawed back numerous areas with military backing from Russia and Iran.

ABC/Reuters

Topics: unrest-conflict-and-war, world-politics, foreign-aid, syrian-arab-republic

First posted February 27, 2018 22:57:30