22/01/2014 12:40 GMT | Updated 24/03/2014 05:59 GMT

Starvation Is a War Crime - The World's Message to Parties of the Syria Conflict

"If you can't stop the war then at least send us steel shelters so children have somewhere to hide, and send us some food so that people don't starve. The children in Syria are so hungry they are eating mud."

These are the stark words of 12-year-old Syrian refugee Zeina to world leaders ahead of peace talks this week, which will determine her country's fate.

In some ways Zeina is one of the 2.4million lucky ones because she was able to escape - that's if you can call being a refugee living in awful conditions in a strange country, with no chance of an education luck. Zeina left Syria with her mother and four brothers two months ago from their home in Aleppo, a city that has been in almost constant bombardment since the conflict began nearly three years ago. Their house was destroyed when Zeina was in the shower. She looks down at her feet as she describes how she ran screaming into the street naked.

Zeina describes scenes of almost unimaginable horror - people forced to forage for mud and roots to eat, children crying with hunger pains as well as fear. These are images we more commonly associate with famine than war. But that's because in our televised, often sanitised view of war we have forgotten that an age-old way of forcing a people into submission is to starve them. Genghis Khan did it nearly a millennium ago; we've seen it through too many conflicts of the 20th Century in Biafra, Sudan, Ethiopia and Somalia, and closer to home in Bosnia. In Syria today it is a deliberate targeted response. The barbarity of Syria's conflict is medieval and the sectarian nature of it tragically familiar. For the millions of innocents caught up in the midst of this conflict it is brutally personal.

Take the words of Bilal, a baker from the city of Homs. He describes how his bakery was repeatedly targeted by snipers every time they attempted to open. "I don't understand it. If you want to kill your terrorists or enemy that's one thing, but why kill old ladies who are queuing for bread?"

I have spent much of the past year listening to refugee stories like this. Time and time again myself and colleagues in World Vision and other humanitarian agencies have heard of the systematic starving and killing of whole populations in besieged or cut-off areas of Syria.

Although the international community together has reached more than 3million people inside Syria with aid, there remains an estimated 2.5million Syrians we cannot reach.

One of these places is Ghouta, the suburb of Damascus and home to tens of thousands that included 8-year-old Tasnim and her mother Rawda. Now refugees in Lebanon, I met them late last year when they told me first hand what this crisis meant for them.

"Death. There were bombs every day. Destruction. Fear. No food, no bread. We barely ate," said Tasnim.

Her mother Rawda explained: "No bread or flour or rice was allowed to enter Ghouta for three months before the chemical attack there. The guards started using bags of flour instead of sandbags around their checkpoint, just to humiliate us. They said that one bag of flour cost one bullet. The biggest disaster [more than the chemical weapon attack] is the hunger. People in Ghouta have nothing to eat, they are dying of hunger. You come from a big country with power - tell me is this right?"

No it's not right. And it has to stop.

Despite a statement from the UN Security Council in September on improving humanitarian access for these unreached Syrians, progress has been poor. At last week's humanitarian conference on Syria I attended in Kuwait, the urgent need for action on this was a recurring theme. Justine Greening, the UK's minister for international development, said "there are no excuses". US Secretary of State John Kerry said "it is unacceptable that today food is being used as a weapon of war". In Kuwait international donors pledged $2.4billion in aid for Syria this year. This follows $5billion spent on aid already since the conflict started almost three years ago but is less than half of what the nine million Syrians need for 2014 alone. Every pound, every dollar will save and restore lives torn apart by the conflict, but this week's peace talks in Geneva are fundamental for Syrian children still besieged in Aleppo, Ghouta, Yarmouk and beyond the reach of humanitarian aid.

Ultimately, the only real and lasting solution to Syria's humanitarian crisis needs is a political one. In Geneva this week all parties to the conflict must search and strive without rest for a lasting peace for Syria's people and the international community must do all it can to support this. For the seemingly impossible to be made possible - a first step on the long, tough road to peace. But even if there are no breakthroughs for peace this week, the need for an unprecedented international humanitarian response must not be derailed or overshadowed. And a very clear message must be sent to all sides of the conflict that in 2014 deliberate starvation of civilians is a war crime. Zeina, Tasnim and millions more of Syria's children deserve no less.