International efforts to rebuild Syria once the civil war is over should center on agriculture to kick start the economy and quickly improve the livelihoods of the people, a high-level United Nations official said Tuesday.

In an interview with The Associated Press ahead of an international Syria donors conference, the United Nations' Food and Agriculture Organization's Deputy Director General Daniel Gustafson said that in case of a return to peace the impact of funding farming would yield almost immediate results.

"If you invest in that, you are going to get a quick return," he said.

Despite seven years of warfare through much of the Middle Eastern nation which also blighted farmland and destroyed facilities, farming still accounts for about a quarter of Syria's gross domestic product.

UN figures show that some $16 billion in production has been lost because of the war and it will take about as much to get the recovery of farming going again. At the two-day Syria conference opening Tuesday, donors from across the globe hope to commit several billion in assistance to alleviate the pressing needs of Syrians. Over $5 billion was committed last year.

Farming in Syria goes back many thousands of years and the nation was long a breadbasket for the area. When the war started almost half the population was still employed in farming.

And despite the horrific war that ravaged orchards and fields, cut the availability of seeds and fertilizers and sent many millions fleeing, half the output survives to this day.

"The resilience of the agriculture sector is an astonishing story. You still have half the production of wheat of what you had before the war" — two million tons, instead of 4 million before the war, Gustafson said.

Still, some 6.5 million people are in urgent need of immediate assistance because they face a lack of food, said Gustafson.

While most of the attention goes to shocking events like bombings or even gas attacks, war in the countryside often has a more creeping effect.

"It is this continuous deterioration of their livelihoods. You cannot get seeds, you cannot sell stuff, you cannot trade, you cannot get spare parts," Gustafson said. "The whole thing just kind of grinds down."

He said that fortunately, the situation can also pick up again soon once the conditions are right, once the right seeds come in again and people and goods are again free to move around the country.