UN Secretary General Ban Ki-moon said Wednesday at a world food summit in Rome that the fight against global hunger was "only just beginning," according to dpa. "We simply cannot fail," Ban told a news conference at the headquarters of the UN Food and Agriculture Organization (FAO), where the meeting is being held. Ban was speaking at the UN Conference on World Food Security, amid negotiations by delegates from 50 nations attempting to forge an agreement before talks end on Thursday. The highest food prices in three decades have exacerbated a crisis in developing nations where 850 million people were already facing food shortages, Ban warned delegates at the opening on Tuesday. World leaders needed to agree on longer term solutions to the price increases and other issues threatening food security, such as biofuel production, the UN secretary general reiterated Wednesday. "Food production needs to rise by 50 per cent by the year 2030 to meet the rising demand," the UN secretary general said. However more urgent measures were also needed, for example to ensure the success of next year's agricultural harvests, Ban said. Farmers in the northern hemisphere needing to plant their crops by the end of July required immediate supplies of seeds and fertilizers, FAO Director General Jacques Diouf, told the same news conference. Diouf, who urged donor nations to come forward with more aid, thanked the Saudi Arabia-based Islamic Development Bank for pledging 1.5 billion dollars over five years for food provision and agricultural production. The head of the UN World Food Programme (WFP) was rolling out an additional 1.2 billion dollars in food assistance, WFP Executive Director Josette Sheeran said. Also speaking at the news conference was World Bank President Robert Zoeelick, who said all emergency efforts should focus on "the 20 most vulnerable countries." "With 2 billion people struggling every day to put food on the table," food production needs to feature high at the G8 summit scheduled in Japan in July, he said. FAO has listed 22 countries that are particularly vulnerable owing to a combination of high levels of chronic hunger - defined as more than 30 per cent undernourishment - and being net importers of both food and fuel. Countries such as Eritrea, Niger, Comoros, Haiti and Liberia are particularly affected. Also Wednesday, a partnership was created involving the Alliance for a Green Revolution in Africa (AGRA) - a group headed by former UN secretary-general Kofi Annan - FAO, the WFP and the UN International Fund for Agricultural Development (IFAD). The agreement aims at "optimizing food production in areas with relatively good rainfall, soils, infrastructure, and markets-or 'breadbasket areas'," FAO said in a statement. After Tuesday's inauguration ceremony, summit activities on Wednesday were largely lower key as working groups engaged in technical discussions around food-production related themes including biofuels, climate change and trade barriers. In a separate development, FAO issued an apology to an Iranian- born journalist, Ahmad Rafat, deputy director the Adnkronos International news agency, who was prevented from attending the summit on Tuesday. "I hope that Ahmad Rafat will accept FAO's apology, as well as my own personal apology, for this unfortunate incident," said FAO communications director Nick Parsons. Rafat, who had been regularly accredited for the summit, was turned away by security officials, who, FAO initially said, were acting on the orders of Italian authorities. This was later denied by the Italian government which said it had demanded an explanation from FAO for the incident.