More than two million children are at risk of malnutrition in Syria, a charity has warned.
Those caught up in the conflict have been left unable to produce or buy enough food while prices have soared and the food production industry has collapsed, Save the Children said.
In rural areas of Damascus one in 20 children is severely malnourished, with 14% classed as acutely malnourished.
The aid agency said it has gathered testimonies from refugees in neighbouring countries as well as residents trapped by fighting and enduring siege-like conditions who have detailed families' desperate struggle to feed their children.
The charity reported accounts of children forced to live off nothing more than lentils or bread for days on end - with one family trapped in their basement by explosions eating just half a piece of bread each, over the course of four days.
Food shortages are leading to a huge increase in food prices, with the cost of the most basic supplies increasing by 100%.
Meanwhile, Save the Children said Syria's agricultural output has dramatically decreased, with grain production falling to less than half of what was typical before the war.
The charity's chief executive Justin Forsyth said: "The world has done too little too late. The children of Syria have been shot, shelled and traumatised by the horror of war. The conflict has already left thousands of children dead and is now threatening their means of staying alive.
"That some children are going to bed trapped amid fighting - terrified, alone, vulnerable - and with empty stomachs ought to be a stain on all our consciences.
"Even if the world cannot agree on how to end the conflict surely they can agree that aid should be able to reach every child in need in Syria. There is no room for delay or argument: Syria's children must not be allowed to go hungry."