A spokeswoman for the International Committee of the Red Cross told CNN Friday that the organization hoped to bring aid to the rebel-held town "in the coming days."
Madaya is reported to be on the brink of starvation, with skeletal people drinking soup made from leaves and grass.
"The convoy is still in preparation," said spokeswoman Dibeh Fakhr. She said the Red Cross hoped also to deliver aid to the northern towns of Foah and Kefraya, which, unlike Madaya, are loyal to the Assad regime
"One short delivery will not be the solution," Fakhr said. "What is needed is regular access."
Food is available... but expensive
The situation in Madaya is said to be dire. Even when food is available, the prices are prohibitive.
In the Syrian capital of Damascus, for example, flour costs 79 cents a kilo. In Madaya, it costs $120. And in Damascus, milk costs $1.06 a liter. But in Madaya, the price is $300.
So those in desperate need can only look at food they cannot afford.
The graphic images of death and starvation coming out of Madaya have not been independently confirmed by aid groups or CNN. However, the United Nations said Thursday it had received "credible reports" of people dying of starvation
and said that the Syrian government had agreed to allow aid convoys into Madaya, Foah and Kefraya.
There are conflicting reports of how many people have died.
The aid group Médecins Sans Frontières puts the number at 23 since December 1
. One activist says it could be as high as 41. The U.N. statement Thursday provided only one confirmed death, that of a 53-year-old man on Tuesday whose "family of five continues to suffer from severe malnutrition."
Help is on the way
The U.N. World Food Programme, or WFP, was preparing to deliver humanitarian aid in the coming days. The convoy -- a partnership between the WFP, the International Red Cross and the Syrian Arab Red Crescent -- would have enough aid to sustain 40,000 people for a month, according to spokeswoman Abeer Etefa.
Madaya, a town of 40,000 people northwest of Damascus, has been under siege since July, cut off by forces of both the Syrian government and Hezbollah, its Lebanese ally. Madaya is also peppered with landmines, thwarting aid efforts.
"People are living off nothing," Etefa told CNN's Christiane Amanpour on Thursday. "This is an area that's completely besieged and surrounded by mountains covered in snow, so the little food that gets in is through tunnels and is extremely expensive."
Pleas for help on social media
Posts on Twitter and Facebook from people who say they live in the town beg the world for help, saying they have no access to food, water or electricity for days at a time.
In one, a man speaks to the camera and breaks down. "What did we do? What did we do?" he cries. "My children, they're dying. Bring guns, bring angels, but God, help us," he wails.
This video, which CNN cannot independently verify, is one of dozens posted online by activists and residents in Madaya. All say they are being starved to death.
In another video
, a child says he hasn't eaten for seven days and wants to eat meat. In another
, a mother says her daughter has not had milk for a month. Again, neither video can be independently verified.
Children eat soup made from leaves and water, one activist, Sham Abdullah, told CNN. He said 41 people had died so far from starvation; other activists and residents have posted images of bodies on Twitter.
One video shows an old woman stirring a pot of green boiling water. The man filming her asks in Arabic: "Hajji, what are you cooking?"
"Grass for the old man," she replies.
Food is available, resident Amjad Almaleh told CNN, but few can afford it.
"Who has that money to feed their families?" Almaleh asked. Just as others have claimed, he says parents feed stray cats and dogs to their children to keep them alive. When they can't find animals, salt and water must suffice.