Rebel fighters help Syrian civilians to gather at a meeting point Wednesday before being evacuated during a U.N.-led humanitarian operation in the besieged Syrian city of Homs. (Bassel Tawil/AFP/Getty Images)

In besieged areas of the Syrian city of Homs, even evergreen trees were stripped bare this winter.

Evacuees who fled in a U.N.-brokered cease-fire, which was extended for three days Thursday, describe being driven to desperation — eating leaves, foraged plants, cats and earthworms.

The aid deal that has allowed civilians to flee and aid to travel into rebel-held neighborhoods of Old Homs, where food supplies have been scarce for the past year and a half and nonexistent for months, has provided a small glimmer of hope as a second round of peace talks in Geneva remain deadlocked.

After sideline talks with the United States and Russia on Thursday, U.N. envoy Lakhdar Brahimi said, “Failure is always staring at us in the face.”

He described the deal in Homs, and the extension of the cease-fire there, as a positive development that he hoped could be replicated elsewhere, but without the need for “a miracle for our people to come out alive” — referencing aid convoys that have been targeted with mortar shells.

Abu Nizar, 72, who lived all his life in the Old City, fled with the first batch of evacuees a week ago.

One in his group was shot in the stomach by a sniper as it crossed through open ground flanked by U.N. vehicles. But Nizar was not deterred.

He was desperate — and it was not his first attempt to leave.

Seven months ago, he tried to escape through a tunnel that had been used for smuggling precious supplies of food in and out of the area, but he said it was blown up by Syrian government forces and partially collapsed while he was inside.

After the tunnels were closed, the situation got worse, and for the past three months, he said, he ate no bread, wheat or rice.

The opposition has accused Syrian President Bashar al-Assad of using starvation as a weapon of war, and the United Nations says that as many as 200,000 civilians are living under siege across the country.

“I’d eat worms,” Nizar, who used a nickname for security reasons, said in a Skype interview. “It’s so disgusting, but we had to eat.”

Occasionally food was scavenged from abandoned houses, he said, but those pickings had become increasingly scarce.

“If we found some olives in a house, it would be a magnificent meal,” he said. On foggy days, they would forage for alfalfa, the mist giving them cover from snipers on the open ground it grew on.

He described his taste of a banana, handed to him by humanitarian workers after he left, as “like being born again.”

Another evacuee, Abu Jalal Tilawi, said that he had been forced to kill and eat cats — and that if there were any left in Old Homs, he would not have left his ancestral home.

“The bombs couldn’t get us out, but the hunger won the game,” said the 64-year-old, his voice cracking with emotion as he spoke. “People would gather grass. We were like herds of animals.”

When the World Food Program made its first deliveries this week, Matthew Hollingworth, the agency’s Syria director, said he had never come across scenes of such destitution. “People were living in their basements, crawling between them in tunnels, existing, not living,” he said.

About half of the 2,500 civilians that were estimated to be trapped in the Old City have been evacuated.

Under the terms of the cease-fire deal, men between the ages 15 and 55 must undergo questioning by Syrian security forces before leaving, and with living conditions so desperate, hundreds have decided to take the risk.

Abu Jalal said that state security attempted to take him for questioning but that a U.N. official intervened.

“He shouted at them and said we are old men and cannot be arrested,” he said. “We managed to leave.”

Hollingworth said there is “extreme concern” for those that remain. Nizar and Abu Jalal have sons who have stayed.

But even those who have left fear that the cycle will only repeat itself. Upon their exit, evacuees were able to choose where they would be taken, with many choosing the neighborhood of Al-Waer, which is partially under rebel control.

However, Abu Jalal said that food is scarce there, too. When he tried to leave the area to buy groceries this week, he said, he was turned back at a government checkpoint.

“I’ve told people to start raising cats and dogs because you never know when you are going to need to eat them,” he said. “Once the world has stopped watching, it will happen here, too.”