U.S. President Barack Obama has announced a new global partnership to improve food security, saying the United States has a "moral obligation" to lead the fight against hunger and malnutrition.

President Obama announced the partnership between governments, donor countries and the private sector Friday. His speech marked the beginning of high-level talks as leaders of the _Group of Eight_ (http://www.cfr.org/global-governance/group-eight-g8-industrialized-nations/p10647) nations gather for their annual economic summit at the Camp David presidential retreat outside Washington.

Obama said the food security effort is aimed at boosting farmers' incomes and helping 50 million people lift themselves out of poverty over the next 10 years.

The U.S. president addressed African leaders from Ethiopia, Ghana and Tanzania during the speech in Washington, which he said will be the first three countries to undertake the effort. African Union chair and president of Benin, Thomas Boni Yayi, is also attending the summit and will take part along with his fellow African leaders in what Obama described as a "special" G8 session Saturday devoted to the food security challenge.

The president touted a global food security initiative the G8 launched in 2009 that resulted in $22 billion in pledges to boost agricultural investments in poor countries, but he said there is still a lot more work to do.

"Despite the fact that African farmers can be some of the hardest working people on Earth, most of the world's unused arable land is in Africa," Obama said. "Fifty years ago Africa was an exporter of food. There is no reason why Africa should not be feeding itself and exporting food again. There is no reason for that. So that's why we're here. In Africa and around the world, progress isn't coming fast enough."