Relentless bombardment by the Syrian military of the rebel enclave of Eastern Ghouta is hampering vital relief operations, an international aid group warned on Friday.
The intensity of the air strikes, which have killed more than 220 civilians in just four days, has made it extremely difficult for relief workers to assist the estimated 400,000 people who live in the enclave under siege, CARE International said.
"Our partners are having a hard time moving around, so how can they reach vulnerable people?" the group's communications director for Syria, Joelle Bassoul, asked.
A CARE-supported community centre in the town of Douma was among the buildings hit, forcing those using it into underground shelters.
More than 4,000 families in Eastern Ghouta are living in basements and bunkers, according to Save the Children.
The enclave, just east of the capital, is supposed to be one of four "de-escalation zones" declared last year in a bid to reduce the bloodshed.
But Damascus has intensified its bombing of the district's towns and is also conducting a major offensive in another of the zones -- Idlib province in the northwest.
UN aid officials appealed for a month-long humanitarian truce to allow aid to be delivered and the sick and wounded brought out for treatment.
But on Thursday the Security Council failed to back the proposal which regime ally Moscow described as "not realistic."
Bassoul warned that without a truce, the consequences for civilians would be disastrous.
"If there is no ceasefire, if this is all left unheard, we cannot imagine the scale of the humanitarian disaster," she said.