GENEVA: The World Food Programme (WFP) has estimated that $13 million to $14 million worth of food products destined to people in need in Sudan have been looted since fighting broke out last month, the WFP said on Thursday.

Country director Eddie Rowe, speaking to Reuters from Port Sudan via video link, described pillaging in the country as rampant and that some reports of WFP's supplies being stolen were still being verified.

"We've estimated that close to 17,000 metric tons have been looted, some in our warehouses, while others on wheels," Rowe said. "This would translate to about 13 or 14 million U.S. dollars - just the cost of the food. Almost every day we are receiving reports of additional looting."

Rowe's comments come a day after U.N. aid chief Martin Griffiths appealed to the warring sides in Sudan to ensure safe passage of humanitarian aid and staff.

$445mn needed to help 860,000 who could flee Sudan by October: UN

The conflict in Sudan has forced about 100,000 people to flee to neighbouring countries, according to the U.N., and has hindered aid deliveries in a country where about one-third of people already relied on humanitarian assistance.

Rowe said that the WFP needed to purchase more supplies urgently for Sudan.

"We know that if we do not procure commodities now, we are going to run out of stock in the next two to three months," he said.

"We've already started our engagement with our donors to see how quickly we can procure and also deliver in these locations where we do have windows of opportunity and where it's considered relatively safe for us to provide assistance," he said.