Washington, May 03 (bdnews24.com/Reuters) - The African Development Bank pledged $1 billion more for food aid on Friday as soaring commodity prices raise fears of famine, and it urged grain-exporting countries not to restrict shipments.

The bank said in a statement that its agriculture portfolio will grow to $4.8 billion, and it was restructuring a portion of that to free up $250 million to be used more quickly.

Wheat and other food prices soared to record highs this year because of strong global demand, unfavorable growing conditions in many regions, ethanol production that diverted a large portion of the U.S. corn crop, and investors pouring money into commodities markets.

The World Bank and other international aid agencies have urged more funding for food aid. U.S. President George W. Bush called for $770 million in new food aid donations and other measures on Thursday.

Countries including India, Vietnam, Indonesia and Brazil have imposed curbs on food exports in a bid to secure domestic supplies and limit inflation.

The African Development Bank said stopping exports "will compromise the existence of about 150 million people in a dozen African states" and urged countries not to restrict shipments.