One of the UN’s largest international relief efforts is under investigation after it emerged that thousands of sacks of food aid were being diverted from starving refugees and openly sold for profit.

The head of the UN’s $955 million (£580 million) aid operation in Somalia has launched an inquiry after being shown footage showing tonnes of food bearing the World Food Programme (WFP) logo widely on sale in Mogadishu, the capital.

Stacks of bags of maize and wheat and tins of cooking oil — marked “not for re-sale” and bearing the UN stamp — are on sale from ten warehouses and 15 shops in the city’s main market.

About 45,000 tonnes of WFP food are shipped to Somalia from Kenya every month. Mogadishu traders told Channel 4 News that they bought their supplies straight from UN staff. “We buy [food] aid from WFP staff directly or from people they employ,” one market trader said.

“They take us to the warehouses used by the WFP and let us load our lorries. The goods are freely available and you can buy as much as you like, but we usually buy no more than 500 to 1,000 sacks at a time. Just a tonne or half a tonne a day can be shifted more discreetly.”

The food could hardly be more needed. More than a million people have been driven from their homes by fighting in the area, including 117,000 thought to have fled from Mogadishu in the past month.

UN officials say that civil war and the worst drought in a decade have created “near-famine conditions”, with Somalia ranking alongside Darfur as the worst humanitarian emergency in the world. The WFP is charged with feeding 3.5 million Somalis — almost half the population — and is struggling to overcome an operational shortfall of more than $84 million over the next six months.

Britain gave the WFP £9 million for Somalia last year through the Department for International Development and is now deciding whether to give more.

Another market trader described how he invented fictional refugee camps, which were then allocated food that he could sell. “You go to the WFP office and fill in an application form to create a camp,” he said. “When we receive the food, we give out some and then divide the rest between ourselves and the WFP guys who negotiated the deal.”

The scam is, according to Mark Bowden, the former British diplomat who is now the UN’s humanitarian coordinator for Somalia, “disturbing”. He is urging the WFP to speed up its inquiry.

Many of the sacks for sale are marked: “A gift from the American people”, with the US government’s aid agency, USAID, providing $274 million last year in food and in humanitarian assistance for Somalia.

Peter Goossens, the WFP’s Somalia director, describes food for sale as a “minor phenomenon”.

Jonathan Rugman’s report on Somalia is on Channel 4 News at 7pm

A nation in need

3.25 million people in Somalia are in need of food aid

One in four children dies before the age of 5

One in six children under this age is acutely malnourished

57,000 tonnes of food aid is being delivered to Somalia — enough for two months

90 per cent of it is delivered by ships, guarded by naval vessels to deter pirates

Source: World Food Programme

Times Recommends

• 'Lost' cargo ship Arctic Sea gives up its secrets
• Army wants to retreat in Afghanistan
• Jungle angel was Obama’s mother