Rising food costs pose as great a threat to world prosperity as the global credit crunch, British Prime Minister Gordon Brown warned Tuesday - saying the crisis will likely reverse progress in the developing world and plunge millions into extreme poverty. The British leader said urgent action to stimulate food production is needed, including a review of the impact of biofuels on global agriculture. Brown was meeting in London with World Food Program executive director Josette Sheeran, development charities and farmers. Rising food prices, stoked by increased fuel costs, have led to the first global food crisis since World War II and sparked protests across the Caribbean, Africa and Asia. "Tackling hunger is a moral challenge to each of us and it is also a threat to the political and economic stability of nations," Brown said, in a statement released Tuesday before the meeting in London.