In a twin-track strategy, Ban said the international community must take immediate steps to increase food availability to vulnerable people as a short-term response.
He called on developed countries to help poor countries expand food assistance through food aid, vouchers or cash, scale up nutritional support and improve safety nets and social protection programs to help the most vulnerable.
Small farmers' food production should be urgently boosted by distributing seeds and fertilizers in time for this year's planting seasons, Ban said.
Some actions have been taken at international level to meet immediate needs.
The World Bank announced last week the establishment of a 1.2 billion US dollars' financing facility to boost food production, including 200 million US dollars in grants targeted at the world's poorest countries.
The FAO also called for 1.7 billion US dollars in new funding to provide low-income countries with seeds and other agricultural support.
The UN chief in particular warned against food export restrictions imposed by certain countries in the face of higher food prices on the global markets to ensure domestic supply.
"Some countries have taken action by limiting exports or by imposing price controls... They only distort markets and force prices even higher," Ban said.
"I call on nations to resist such measures and to immediately release exports designated for humanitarian purposes," he added.
Ban also urged developed countries to open markets for agricultural products from developing countries and eliminate subsidies to farmers, a thorny issue hindering the World Trade Organization (WTO) Doha Round negotiations.
The international community must act for longer resilience and contribute to global food security by "eliminating trade and taxation policies that distort markets, not least through rapid resolution of the Doha Round," he said.
Developing countries have long complained about heavily subsidized food from Europe and the United States being dumped on their markets, damaging their own farmers.