U.N. officials announced almost $3 billion of emergency aid to help ease the global food crisis on Wednesday, but U.N. chief Ban Ki-moon warned up to $20 billion a year would be needed. "We simply cannot afford to fail," said Mr.-1 Ban at the food security summit in Rome, which is grappling with how to stop the crisis escalating. "Hundreds of millions of people expect no less." The extra resources that might be as required will cost between $15 billion and $20 billion a year, Mr. Ban told a news conference. New funding totalling some $2.7 billion was announced on the second day of the summit in Rome, where Mr. Ban has already demanded a 50 per cent increase in food production by 2030. Food prices have doubled in three years, according to the World Bank, sparking riots in Egypt and Haiti and in many African nations. Brazil, Vietnam, India and Egypt have all imposed food export restrictions. Leaders at the Rome summit were finalising an action plan to be unveiled on Thursday, said Mr. Ban, while warning that it would require "substantial and sustained financial and political commitment." John Holmes, head of the U.N. task force on the food crisis, said a "broad consensus" was building around the action plan.