The head of the UN Food and Agriculture Organisation has warned another food price crisis might happen if record high energy prices, growing demand for bio-fuels and low grain reserves force up price benchmarks.

The prices, which have been steadily rising since 2007, have caused riots in many countries where some of the population have been unable to afford high priced food.

Food prices have remained especially high in many developing countries, with the threat of another global price hike persisting.

Jacques Diouf has told VOA that energy prices are above pre-crisis levels and crops are still being diverted for bio-fuels.

He said with extreme weather becoming more frequent and the world's population expected to grow by nearly 50 percent to 9 billion by 2050, developing countries would grow the most, requiring more nations to invest more in agriculture.

Last summer in Italy, the G-8 group of industrialized nations pledged $20 billion to help farmers in the developing world expand food supplies.