At a food summit in Rome next week, the international community must recognise that poverty challenges have changed and agree to reverse years of neglecting poor farmers, said the head of the International Fund for Agricultural Development.

"They (governments and donors) have taken cheap, affordable food on the international market for granted. We no longer can do that and we have to realise it's a profound structural problem," IFAD President Lennart Bage said in an interview late on Monday.

Initially called to address the effects of climate change on food security, vast food price hikes that continued well into this year have shifted the summit's focus to what U.N. Secretary-General Ban Ki-moon has called a "global crisis".

Although not a donors' conference, world leaders are due to agree a statement on how to address food shortages and a task-force set up by Ban will issue an action plan.

Bage said a period of global abundance, which ran for 25 years from the early 1980s, had made some countries complacent.

"Many African leaders have said to me: 'Why should we use scarce resources for agriculture when there is abundant and cheap food available on the international market'.

"We were lulled into complacency that there's abundant and affordable food available -- that's not longer the case."

A range of factors have contributed to the price surges, including poor harvests in some exporting countries, record low stocks and rising oil prices driving up costs.

But the fundamental challenges of a growing population and rising demand for a richer diet in places such as India and China will not go away, Bage said.

"Never in any period in human history have so many people moved out of poverty as in the last 20 years.

"That's a good thing but we need to see to it that it's workable in an environmentally sustainable way. We need to re-engage in the very basis of human existence -- namely food."

IFAD runs projects aimed at giving long-term help to small farmers and is involved in countries worst affected by the food crisis, such as Haiti.

People died in the Caribbean nation in food riots that toppled the government in April and future harvests are threatened as people have had to eat seeds meant for planting.

Bage said success stories such as Vietnam, which has helped small farmers to the extent that the country is now a significant exporter of some commodities, such as rice and coffee, showed aiding farmers could work.

Such projects meant the world would be able to feed a population expected to grow by 50 percent by 2050 to 9 billion.

"It is do-able but it won't be automatic," Bage said. "You can't do it on autopilot, you have to engage."