UNITED NATIONS: Many of the world's poorest people are unable to get enough food because of soaring prices partly caused by the use of food crops to produce biofuels, the head of the U.N. food agency said. "We're seeing more people hungry and at greater numbers than before,' Josette Sheeran, executive director of the Rome-based World Food Program (WFP), said in an interview Monday with The Associated Press. Higher oil prices are contributing to steeper food prices by boosting transportation costs, and severe weather is also hitting many countries and hurting crop output, she said. "We're seeing many people being priced out of the food markets for the first time,' said Sheeran, who was at U.N. headquarters for a General Assembly debate on global warming. "For the world's most vulnerable, it's extremely urgent,' she added. The WFP provides food aid around the globe, and Sheeran said the amount of food the agency can afford to buy for hungry children is down 40 percent from just five years ago. One of the problems is the drive to use corn, soybeans, sugar cane and other crops to produce biofuels, which are seen as a cleaner and cheaper way to meet soaring energy needs than greenhouse gas-emitting fossil fuels. That has led to less grain being available for food, driving up prices for basic foods in many countries. Another U.N. agency in Rome, the Food and Agriculture Organization, said Wednesday that some 100 million tons of cereals are being diverted to the production of biofuels each year. Nearly all of that is corn - 12 percent of all the corn consumed around the globe, the FAO said. The agency, which promotes agriculture improvements, said the biofuel uses along with growing demand for food has pushed world food stocks to their lowest level since 1982. It estimated food stocks would total 405 million tons at the end of the current season, a 5 percent drop from the start. Sheeran said more must be done to supply food to the neediest while markets adjust to the biofuel demand. "More food will be produced. Farmers will respond, and maybe there'll be investment in the African farmer for the first time, for example, in many decades,' she said. "When that happens we'll get increased food in the food supply system. But there's a lag, so we have people very vulnerable right now who can't afford the food.' Joachim von Braun, director general of the International Food Policy Research Institute in Washington, cited rising demand from high economic growth in developing countries and the production of biofuels as the biggest factor in high food prices. "If you look at both of these factors, the biofuels-related price increases have started to dominate, or lead to a price increase of about 30 percent,' he said. "Most Latin American countries have passed international prices on to consumers and producers, such as Mexico. Some have closed their borders, like Ethiopia and India, and thereby tried to maintain domestic prices. But by doing so they starve their neighbors.' Von Braun said food shortages could be eased by keeping borders open to trade, increasing global research in agriculture and creating special programs to feed more young children. Sheeran said it also would help if biofuel makers focused on using plants that aren't good for food, noting that anything with cellulose can be used for such fuels, citing switchgrass, shrubs and trees as examples. Instead, she said, "we're seeing everything be used from cassava to maize to palm oil to wheat _ all sorts of (food) crops.' Using nonfood crops might bring additional benefits, because those plants often "can be grown on soil that couldn't be used for food,' she added. "This can be a boon for poor farmers around the world. This can help poor countries.' But Sheeran said the World Food Program was not recommending the use of nonfood crops for biofuel, saying that required a policy discussion. The WFP is studying 30 countries it considers to be the most vulnerable to high food prices to determine how many people are affected, Sheeran said. "We know, for example, in Afghanistan there's been an emergency appeal for $77 million worth of food because they simply cannot import the food to fill the shelves,' she said. "Prices are too high.' According to a recent Afghan government and WFP analysis, wheat prices rose more than 60 percent on average in 2007 and as much as 80 percent in some locations. Rick Corsino, WFP's country director in Afghanistan, said: "Afghanistan faces so many hardships _ and now global increases in the price of wheat mean that bread, the basic staple of the Afghan diet, is out of reach for millions of Afghans.' The WFP said Sri Lanka's government reported a 50 percent price increase for rice and a 62 percent jump for wheat flour last year. It said Benin reported a 100 percent leap in corn prices and 13 percent rises for wheat flour and rice just between July and January.