Riots against rising food prices have spread around the world in recent days
US President George W Bush has ordered the release of $200m in emergency aid to alleviate food shortages in Africa and other parts of the world.
The White House said the money would be used to meet unanticipated needs for food aid.
Rising food prices have sparked recent riots in several countries, including Haiti, the Philippines and Egypt.
The World Bank has said a doubling of food prices in three years could push 100m more people into poverty.
"This additional food aid will address the impact of rising commodity prices on US emergency food aid programmes and be used to meet unanticipated food aid needs in Africa and elsewhere," the White House said in a statement.
The announcement followed a call by the World Bank's Development Committee and the International Monetary Fund for rising food prices to be addressed at the highest political level.
Food riot deaths
UN Secretary General Ban Ki-moon said on Monday that the rapidly escalating crisis called for short term emergency measures to prevent people in many parts of the world from starving.
The UN's World Food Programme has launched an emergency appeal for $500m, saying the money is needed by 1 May to avoid food rationing.
Prices have risen sharply in recent months, driven by poor crop-growing weather in certain countries, increased demand and a reduced production area resulting from an increase in the use of land to grow crops for transport fuels.
World Bank head Robert Zoellick had on Sunday proposed a "new deal" action plan for a long-term boost to agricultural production.
Emergency help would include an additional $10m to Haiti, where several people were killed in food riots last week, and a doubling of agricultural loans to African farmers.
The US provided more than $2.1 billion in food aid in 2007.