GENEVA (Reuters) - The 400,000 civilians besieged in the Syrian enclave of Eastern Ghouta face “complete catastrophe” because aid deliveries are blocked and hundreds of people need urgent medical evacuation, U.N. humanitarian adviser Jan Egeland said on Thursday.

Seven people have died because they were not evacuated and 29 more were at imminent risk including 18 children, he told reporters in Geneva after a regular meeting of the U.N. humanitarian taskforce on Syria.

“I feel as if we are now returning to some of the bleakest days of this conflict again,” Egeland said.

“Nowhere is it as bad as in Eastern Ghouta,” he said of the area, which is surrounded by the army.

The area east of Damascus had been “completely sealed off” since September, leaving U.N. aid convoys and evacuations as a potential lifeline facing a “bureaucratic wall of inaction”.

“We cannot continue like that. If we only get a fraction of what is needed it will be a complete catastrophe,” he said. “What about a ceasefire now in this area and a green light to all medical evacuations?”

As well as people wounded in the fighting, there were a growing number of acutely malnourished children, which meant they were very close to dying, he said.

“Why men in their 50s and 60s like me stop women and children from getting the medical service that would save their lives is beyond my imagination. It can change tomorrow.”

Russian, Syrian and U.N. officials had met in Damascus to try to break the deadlock, both for Eastern Ghouta and for about 55,000 civilians stranded on the Jordanian border in a desolate area known as the Berm.

“The first meeting still hasn’t produced at all the concrete results that were needed but it is our strong feeling that the Russian Federation wants us to get the access and wants to help us so we are hopeful that this trilateral mechanism will yield results.”

The Berm had not received an aid distribution since June, but the United States, Russia and others had worked out a detailed plan to supply aid from Damascus.

Despite diplomatic efforts to set up “de-escalation zones” there was still fighting in many areas, including Aleppo, Idlib, Raqqa, Deir al-Zor and Hama, and civilians were being caught in the crossfire.

He said the war had lasted longer than the Second World War, and supplies were depleted, so that the coming winter could be the toughest of the war even if it is the last.

“This is a man-made disaster, it can end,” Egeland said.