The UN's "2006 World Economic and Social Survey" said that -- once China and India were excluded from the calculation -- inequalities between countries around the world had grown sharply in recent decades. Fast-growing China and India account between them for one third of the world's population.

The report said this development was "at odds with the conventional economic wisdom regarding how income differentials among countries change over time in a more integrated world economy".

Only a small number of nations had been able to narrow the chasm that separated them from wealthy economies despite a belief in the 1980s and 1990s that "giving more space to the global market would lead to a closing of the income gap", it added.

"This did not happen ... despite the fact that countries across the globe had opened up their trade and financial systems to the global market," observed the report by the UN's department of economic and social affairs.

It argued that poorer countries needed to be given more opportunity to diversify their commodity-based economies to make them less vulnerable to fluctuations in world prices and shocks in international financial markets.

They should be able to follow the example set by dynamic Asian economies by shifting towards high-tech industrial production and services, it argued.

"Success in exports is basically associated with what you export, not how much you export," UN Under Secretary General Jose Antonio Ocampo told journalists in Geneva.

"To stave off collapses such as those felt in the developing world in 1996-98 and 2000-02, countries should adopt policies adopted to their national situations, breaking free of lockstep approaches to policy-making," he said.