The organisation's executive director, Catherine Bertini, said traditional causes of food crises, such as natural disasters, had produced particularly serious effects this year.

Examples include Hurricane Mitch in Central America, the worst natural disaster to hit Central America in 200 years, and what the WFP describes as the worst floods in Bangladesh for a century.

Vitamin deficiencies lead to blindness

However, Ms Bertini said there were also new triggers for famine.

Economic collapses in Indonesia and Russia, the resumption of civil wars in Kosovo and Angola and long-term conflicts like that in southern Sudan have also driven up hunger levels.

The agency said the economic emergency in Indonesia, had spawned massive shortages of food and medicine and "transformed middle-class citizens into a new population of hungry poor".

Record airdrop

Ms Bertini said more than 800 million people in the world were chronically undernourished.

The WFP is currently co-ordinating the largest humanitarian airdrop operation in history in Sudan, feeding some 1.8 million people to alleviate the effects of 15 years of civil war.

In Bangladesh, the programme is feeding 19 million people in the wake of devastating floods in the largest emergency operation since the organisation was set up 35 years ago.

It has also just launched its first operations in China which also suffered severe flooding this year.

Ms Bertini called on the international community to make food relief a top priority in 1999.