Nairobi - Incoming US president Barack Obama must act to address hunger and poverty in Africa, prominent anti-poverty campaigner Jeffrey Sachs said Monday.

"Obama has a responsibility to accomplish a great deal (in Africa)," Sachs, an economist and Director of the Earth Institute at Columbia University, told journalists in Kenyan capital Nairobi.

"Not because of his African heritage, but because the US has not been fulfilling its responsibilities in this part of the world," he added.

Obama, whose late father was Kenyan, will be inaugurated on Tuesday. Many Africans are expecting a great deal from the new man in the White House.

Sachs criticized the outgoing US administration for failing to meet aid commitments to Africa.

Developed nations have promised to increase aid to 0.7 per cent of Gross National Income (GNI) by 2015 in order to meet the Millennium Development Goals (MDGs), a series of ambitious UN targets aimed at improving the plight of the world's poorest by 2015.

However, the US is currently only committing 0.16 per cent of its GNI to Official Development Assistance - one of the poorest figures among nations committed to the MDGs.

Sachs's visit to the president-elect's ancestral homeland coincided with a food crisis typical of the problems being faced across Africa.

Kenyan President Mwai Kibaki last week declared a national emergency and called for almost 500 million dollars in aid to help feed 10 million people.

Kenya, like many of its East African neighbours, has suffered from failed rains and is thus facing a massive shortfall in food production.

Sachs said that international donors such as the US should give targeted aid to small-scale farmers, giving them access to fertilizers and other modern farming techniques in order to boost food production by up to threefold.

He also called for a change in US policy on contraception and family planning in developed nations, calling unchecked population growth the biggest threat to Africa's future.

The Bush administration took a pro-life stance on Africa, cutting funding to contraception and abortion programmes. (dpa)