In 2050 climate change will decrease food and agricultural production by up to 30 percent in parts of developing countries, UN Food and Agriculture Organization (FAO) director-general Jacques Diouf said on Monday.

Opening the High-Level Expert Forum on world hunger, which is being held here from Monday to Tuesday, Diouf warned that climate change is bound to have a negative effect on the economy of poor and developing countries.

Noting climate change would reduce water availability and lead to an increase in weed, animal pests and diseases, the FAO chief said the combined effects of climate change could reduce potential output by up to 30 percent in Africa and up to 21 percent in Asia by 2050.

The Rome-based agency is hosting the international panel grouping more than 300 academic, nongovernmental and private sector representatives from developing and developed countries. Talks focus on finding solutions to tackle world famine and food emergency in 2050.

Global challenges and efforts in tackling famine will thus be rendered more tough. By 2050 the world's population is set to reach 9.1 billion people and in order to ensure food security Diouf said "agricultural production must increase by at least 70 percent, which means of 100 percent in developing countries."

He called for "the 192 FAO members to find the political and economic responses to fulfill such ambitious goals."

Despite the fact that agriculture is responsible of 14 percent of Co2 emissions (74 percent of which produced in developing countries), FAO's director said the sector "can actively contribute to adaptation and mitigation strategies aimed at tackling climate change."

"We must learn from our past errors and implement an efficient global and local agricultural governance in order to meet current challenges."

Diouf said that "ensuring food security and eradicating hunger in the world is not only a moral, but also an economic duty" and the key is to be found in an increase of investments in the agricultural sector.

"Rural gross domestic product (GDP) growth is twice more efficient for poverty reduction in developing countries than growth created in other sectors,"he said.

The reduction in development aid and investments, Diouf said, drastically dropped by 58 percent between 1980 and 2005. He urged industrialized nations to fulfill their commitments by investing 83 billion dollars a year to feed a growing population.

Other than climate change, the forum discussed the problem of soaring food prices which are likely to stay high and volatile in the medium term.

The experts warned that a repeat of the 2007-2008 price spikes is a realistic possibility. The increase in food prices have caused a sharp rise in the number of hungry people around the world to more than one billion this year.

According to FAO, prices have fallen back since but will remain high and are not likely to drop below their 2006 level. Insufficient investment in productive capacity and further demand growth for bio-fuels were also factors that could keep prices firm in the medium term.

With the theme of How to Feed the World in 2050, the forum is preparing the ground for the World Summit on Food Security, scheduled in Rome on November 16-18.