World leaders gather in Rome on Tuesday for a UN summit on food security as UN Secretary General Ban Ki-moon urged "hard decisions" and heavy investment in agriculture.
"For years, falling food prices and rising production lulled the world into complacency," Ban said, adding: "Governments put off hard decisions and overlooked the need to invest in agriculture."
"Today, we are literally paying the price," he said on the eve of the three-day Food and Agriculture Organization (FAO) summit.
"If not handled properly, this issue could trigger a cascade of other crises -- affecting economic growth, social progress and even political security around the world," Ban warned.
Participants at the High-Level Conference on World Food Security will discuss short-term solutions as well as new strategies to deal with the effects of global warming, growing demand for biofuels and a crumbling agriculture sector in much of the developing world.
The runup to the summit has been clouded by the planned attendance of Zimbabwean President Robert Mugabe, which sparked condemnation notably from Australia and Britain.
Australian Foreign Minister Stephen Smith called Mugabe's presence in Rome "obscene," saying: "This is the person who has presided over the starvation of his people. This is the person who has used food aid in a politically motivated way."
In London, British Prime Minister Gordon Brown's spokesman said: "We think it's particularly unfortunate that (Mugabe) has decided to attend this meeting."
The presence of Iranian President Mahmoud Ahmadinejad also generated controversy.
The Israeli ambassador to Italy, Gideon Meir, said Monday: "It was inopportune to invite him, since it gives him a forum to speak in and to shake hands with other leaders," the ANSA news agency reported.
Ahmadinejad, who was to hold a news conference at the FAO on Tuesday afternoon, repeated his controversial belief that Israel will soon disappear.
"I must announce that the Zionist regime (Israel), with a 60-year record of genocide, plunder, invasion and betrayal is about to die and will soon be erased from the geographical scene," Ahmadinejad said.
Meanwhile, Japanese Prime Minister Yasuo Fukuda said in London that Tokyo would use the outcome of the Rome summit to focus debate at a Group of Eight summit it is hosting in July.
"This is a multi-faceted problem that calls for multi-faceted response," Fukuda said. "We would like to build on the outcome of (the Rome) meeting and engage ... at the G8 on the various complex factors behind rising food prices" worldwide.
The humanitarian charity Oxfam accused the international community of spending a "pittance" on supporting agriculture in developing countries compared to the huge support given to farmers in rich Western countries.
"World leaders must urgently agree a coordinated global action plan to address the food price crisis," the group said Tuesday.
Ahead of the summit, battle lines were drawn over the causes of the crisis.
Oxfam staged a protest on Monday to dramatise the effects of the rising use of biofuels, with three actors dressed as ears of corn being strangled by a petrol pump hose.
But Oxfam stressed that European and North American biofuel policies are only one of several factors causing higher food prices.
Estimates vary on the extent to which demand for biofuels has pushed up food prices.
The International Food Policy Research Institute, based in Washington, estimates that it accounts for 30 percent of the increase, the International Monetary Fund puts the figure at 15 percent, while the US Agriculture Department says it is under three percent.
On Sunday, dozens of non-governmental organisations and small farmers' groups opened an alternative forum to coincide with the FAO summit.