"We are facing the risk that the number of hungry will increase by many more millions of people."
Should prices continue to rise at their present rate, by the end of 2008 the annual food import basket for Low Income Food Deficit Countries (LIFDCs) could cost four times as much as it did in 2000.
Rising food prices have led to protests around the world in recent months.
A senior UN body also said on Thursday that the fallout from the rising cost of food around the world constituted a threat to basic human rights.
Louise Arbour, UN High Commissioner for Human Rights, told the UN Human Rights Council that the "well-being and rights of countless people" was being threatened by the soaring cost of corn, rice, wheat and other staple foods.
"This crisis boils down to a lack of access to adequate food. Such access is a right protected by international law," she said.
The UN says high oil prices, growing demand, bad trade policies, bad weather, panic buying and speculation, are among the reasons for a rise in the cost of food.
Olivier de Schutter, UN rapporteur on the right to food, told Al Jazeera that food import bills for developing nations had increased "significantly" since 2006.
"[The import bill rises] add up to the increases in the price of oil, which, of course, is necessary for the payment of transportation costs of food imports," he said.
"Certain states are doing quite well; developing social safety nets, providing cash to the poorest sectors of the population or in developing food stamps programmes, such as in the Philippines and India.
"Other countries have immense difficulties in insulating their populations from these skyrocketing prices."
The FAO report also said that the cost of rice, which has soared in recent months, may drop as new crops are harvested around the world.
But it said that prices will remain high at least until October or November, when harvests from paddy fields reach the market.
Some nations, including the Philippines, have suspended rice exports to allow its own people to gain access to the staple food.
"One thing is to say prices will come down, which is already happening for many products," Abdolreza Abbassian, an FAO economist, said on Wednesday.
|Some countries had suspended rice exports as|
a result of the rising cost of staple foods [AFP]
"Another is to say they will be low. No, they won't be low."
The FAO report forecasts record output of cereals in 2008, although prices throughout the year will remain volatile owing to tight markets.
And it says international prices for oilseed have climbed to record levels amid reduced supply growth and increased demand.
Meat output is also predicted by the FAO to rise throughout this year, even though the cost of animal feed is increasing.
Economic growth across the world is fuelling meat production in many developing countries, but the demand for meat has diverted staple crops from people to animals, hitting poor countries.
The FAO also said in its report that potato production in developing countries could rise by two and three per cent each year over the next decade.
A move by several countries to move towards potatoes as a staple food is considered to be one of the reasons why production of the vegetable is rising.
Although conditions for food production are favourable, the report says, a drop in prices for agriculture commodities will only be limited during the 2008/2009 season because food stocks need to be replenished.
Read the FAO's Food Outlook report in full
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