UN chief Ban Ki-moon will prod world leaders to step up the fight against global warming and hunger when he attends the UN Food and Agriculture Organization summit in Rome next week, according to a spokesperson.

"The secretary-general will open the food security summit to promote broad based action on food security," deputy UN spokeswoman Marie Okabe said.

"This is an important opportunity following significant advances under the L'Aquila initiative on global food security chaired by Prime Minister Silvio Berlusconi" in July in Italy, she said. "Given the close interrelationship between food security and climate change, the secretary-general will engage world leaders to advance both agendas together," she added.

Non-governmental organisations called on the Group of Eight developed nations to keep their promise made in L'Aquila to fund a 20-billion-dollar world food aid programme. They lamented, however, that none of the G8 leaders will be at the FAO summit.

Mr Ban's November 15-17 visit to Rome will include a tribute at FAO's headquarters to five UN employees killed last month in a suicide bombing of a UN World Food Programme compound in Islamabad, Okabe said.