Despite global efforts to eradicate grinding poverty, the poorest countries are on course to grow poorer still as their natural resources dwindle, the World Bank said Tuesday ahead of the UN summit.
In a report released on the eve of the three-day summit, the global lender warned that the UN's "Millennium Development Goals" (MDGs) were at risk from unsustainable environmental policies.
"There is a shared sense of urgency about meeting the MDGs," said Ian Johnson, World Bank vice president for sustainable development.
"However, it would be tragic if the achievements of 2015 are not sustained because soils have been mined and fisheries and forests depleted," he said.
At this week's UN summit, world leaders are set to measure progress made towards the MDGs set in 2000, which include a target to halve global poverty and hunger by 2015.
Campaigners have long argued that the 2015 targets will be missed, accusing rich countries of failing to live up to their promises. Africa is seen as the continent least likely to meet the UN goals.
The World Bank report, entitled "Where is the Wealth of Nations?", said the broadest measures of wealth should evaluate natural resources, savings rates and population growth.
On that basis, the world's poorest countries are in fact going backwards. Ethiopia is the least well off overall, followed by Burundi, Niger, Nepal and Guinea-Bissau.
The five richest countries as measured by the report's criteria are, in descending order, Switzerland, Denmark, Sweden, the United States and Germany.
The report lays bare the yawning disparity between the wealth levels of the richest and poorest countries, and just how much natural resources matter to developing countries.
Switzerland has a "wealth per capita" of more than 648,000 dollars. It relies on "natural capital" to generate just one percent of its wealth, compared with 15 percent for "produced capital". For Ethiopia, the figures are 41 percent and nine percent respectively. Its wealth per capita is a meagre 1,965 dollars.
The seventh of the eight MDGs calls on countries to "ensure environmental sustainability", defined as reversing the losses of natural resources by 2015. "Achieving this goal has proven to be elusive for most countries, not least because of a lack of indicators of sustainable development," the World Bank report said.
"If a household is running down its bank account from month to month, or having to sell assets such as vehicles or livestock in order to keep food on the table, then we would conclude that this household is not sustainable," said the report's main author, Kirk Hamilton.
"The same applies to nations as a whole - if their net saving rate is negative then this is a signal that national wealth is being run down and the development path is not sustainable," he said.
The report singled out some developing countries for their sensible husbanding of scant resources. Mauritania has boosted its development prospects through better management of fisheries. Botswana has successfully used diamond resources to finance schooling, healthcare and infrastructure building.
"Sound management of ecosystems is key to a responsible path to growth," Johnson said.
"This publication challenges common assumptions about how nations generate their wealth," he said.