LONDON — A "perfect storm" of drought, conflict and rising costs has increased the ranks of the chronically hungry by millions of people, and forced aid workers to find and fund longer-term solutions to the food crisis.

The United Nations says the number of chronically hungry people worldwide rises by an average of 4 million each year.

At the same time global fuel prices have soared, pushing up road transport costs and global maritime shipping rates.

The UN's World Food Program says the cost of cereals has risen 50 per cent over the past five years, which experts say is due to the world's growing population — particularly in non-food producing urban areas — combined with bad harvests and an increased demand for cereal products in previously rice-eating India and China.