The main quandary in aiding Africa is not the absence of initiatives or technology, but the "lack of adequate financing" by donor countries that fail to follow through on their commitments, U.N. adviser and economist Jeffrey Sachs said Tuesday.

At a news briefing in Tokyo, Sachs, a special adviser to the secretary general of the United Nations, said developed countries at the Group of Eight summit in Gleneagles, Scotland, in 2005 promised to double aid to Africa by 2010.

But the chairman of the OECD's development assistance panel said in Tokyo last month that while sub-Saharan aid is increasing faster than total aid, it's not climbing fast enough to double by 2010.