A single road, like a fragile umbilical cord, connects rebel areas of Syria's second city Aleppo with international relief from Turkey.
Those who remain are stockpiling arms and supplies -- bracing for their redoubt to be completely blockaded by the Syrian regime.
In the Turkish city of Gaziantep, charities are preparing to send aid south of the border to a Syrian city where 250,000 to 300,000 people are still living despite the relentless violence, too poor to escape or too invested in the fighting's outcome to run away.
"But it is under fire from all sides so it is still dangerous. It can be cut off at any moment," he said.
"Preparations are in full swing to get ready for a full siege," Ashi added.
"Syrian humanitarian organizations -- there are around a hundred on the ground -- are stockpiling everything they can inside the city.
"The local council in Aleppo has formed an emergency body to prepare for the siege. In the event of a total siege, Aleppo could last for a year, probably more," he estimated.
President Bashar al-Assad's army began large-scale offensives against the Aleppo rebels in February, backed by an intense campaign of Russian air strikes.
Bombardment by bombardment, strike by strike, fears that the city faces complete encirclement have taken hold, with thousands of civilians displaced by the fighting.
Insurgent groups can still reach the other rebel stronghold of Idlib in the northwest. From there, the Aleppo fighters have stockpiled hundreds -- perhaps even thousands -- of tonnes of weapons and provisions like flour, oil, sugar and medical supplies.
The siege of the southern city of Homs -- where the rebels held out for three years before finally surrendering -- provides a grim example of what Aleppo could face.
"But Aleppo won't be like that," said Manhal Bareesh of the Syrian opposition.
"The rebel zones are much larger and better defended. They are building trenches and tunnels so they can continue to move around. The siege will never be completely watertight."
Many hospitals and clinics, often targeted by air strikes to demoralize civilians and fighters, have been moved to basements, as have some schools. Read more: