A sharp downturn in the global economy is the most likely and most serious threat to the world in 2008, according to a report released Wednesday by the World Economic Forum. Fears of a US recession coupled with a sudden spike in oil prices have replaced terrorism, pandemic disease outbreaks and short-term disasters resulting from climate change as the issues global business leaders are most worried about, said the "Global Risks 2008" report. The document, which is based on workshops with corporate leaders, professors and risk analysts, also listed dwindling food supplies as a growing concern. "A recession in the United States cannot be excluded in the year ahead," the report said, adding that "economists are divided on whether domestic-led growth in Asian markets can drive the global economy." The publication of "Global Risks 2008" coincides with a World Bank study released Wednesday that expressed concern about the faltering US housing market and its impact on global financial markets. The World Economic Forum report said changes in the global financial system over the past few years may have made it more susceptible to instability during periods of crisis. "The complexity and near-infinite feedback loops of the modern financial system have exposed it to a small risk of very large systemic shocks," said the 54-page report, which was published by the Forum in collaboration with Marsh & McLennan Companies Inc., Citigroup Inc., Swiss Reinsurance Co., Zurich Financial and the Wharton School at the University of Pennsylvania. Losses to banks in markets such as Germany and Britain as a result of the US subprime mortgage crisis show how vulnerable the global financial system now is to sudden, unforeseen risks, the report said. The world economy is also threatened by the high cost of oil, particularly if prices rise sharply as a result of political crises or natural disasters, it said. "Over the 10-year horizon of this report, there are few reasons to believe that energy prices will fall significantly, and there are several reasons to believe that energy prices may rise," the report said. The third major risk - dwindling food supplies - has become an issue not just for developing nations, but also for rich countries, the report said, citing steep price increases for staple foods over the past year. "There is considerable uncertainty as to whether food insecurity in 2007 is the result of short-term conditions... or whether a more fundamental change is taking place," the report said. "Policy-makers may have to return to thinking about food as a strategic asset," it said, adding that "the resilience of the world's food system will be severely tested in the next few years." The report, released two weeks before the Forum's annual gathering in the Swiss resort of Davos, also cited a slowing of economic growth in China to 6 percent, the cost of chronic diseases in the developed world, and the uncertain political situation in the Middle East as major concerns for 2008.