"The first and immediate priority that we all agree is that we must feed the hungry," Ban said after a meeting with U.N. agency heads and other top officials.
Ban, who will lead the task force, said he agreed with U.N. agency chiefs on a series of measures for the medium and long term, with the first priority being to meet the US$755 million (euro483 million) shortfall in funding for the World Food Program.
"Without full funding of these emergency requirements we risk again the specter of widespread hunger, malnutrition and social unrest on an unprecedented scale," he told reporters in the Swiss capital, Bern, where the U.N. agency chiefs have been meeting.
"We anticipate that additional funding will be required," he said.
Global food prices, stoked by rising fuel prices, unpredictable weather and increased demand from India and China have sparked sometimes violent protests this year in the Caribbean, Africa and Asia.
Ban said also urgent is the need to ensure food for tomorrow by supporting farmers in poorer countries.
The effort needs to focus on Africa, which could double food production over a very few years, Ban said later in a speech at the U.N.'s European headquarters in Geneva.
It will "cost a relatively modest US$8 to US$10 billion annually," he said.
"The fact is that Africa is anything but a lost continent," Ban said.
Already some African countries are making progress in food production, educating children and reducing child mortality, he said.
"In addition to increasing food prices, we see at the same time farmers in developing countries planting less, producing less, due to the escalating cost of fertilizer and energy," he said. "We must make every effort to support those farmers so that in the coming year we do not see even more severe food shortages."
Ban said there were a number of causes of the food crisis, including climate change, long spells of drought, changing consumption patterns in major developing countries and the planting of crops for biofuel.
He said new measures had to go further than just providing emergency food relief.
The U.N.'s Food and Agriculture Organization has developed a US$1.7 billion (euro1.1 billion) plan to provide seeds for farmers in the world's poorest countries, he said.
"We must make every effort to support those farmers," Ban said.
He said he hoped world leaders would come to a June meeting in Rome to find ways to alleviate the food crisis. He said the international community had previously not listened to warnings from the FAO and others.
"The whole United Nations is now leading this campaign to address this issue," he said.
World Bank President Robert Zoellick, who also attended the meeting, said 100 million people are estimated to have been pushed into poverty over the past two years.
"This is not a natural disaster," Zoellick said.
He said US$475 million (euro304 million) has already been pledged to WFP but more is needed.
"This crisis isn't over once the emergency needs are met," Zoellick said.
"We can't just replay this year after year after year," Zoellick said.
Zoellick urged countries to refrain from using export bans, referring to some Asian countries, including India and Vietnam, which have curbed rice exports to guarantee their own supplies.
"These controls encourage hoarding, drive up prices and hurt the poorest people around the world, who are struggling to feed themselves," he said.