Major world institutions, such as the Group of 7 (G7) and the United Nations (UN) lack the credibility to deal with the global financial crisis, National Planning Minister Trevor Manuel said on Friday.

"The UN has neither the credibility nor the institutional mechanisms to tackle the crisis," Manuel said at the South African Institute of International Affairs in Johannesburg.

"The major institutions that have come to prominence in responding to the economic crisis have not been the ones that were around 20 years ago. The G7 has lost its importance because of the absence of large emerging economies."

The World Bank and the International Monetary Fund (IMF) did have some role to play but transformation in these institutions was unlikely.

"Institutions like the UN have unwieldy decision-making processes and are remarkably change averse.

"Organisations like the World Bank and the IMF lack the credibility and in these institutions too, vested rights trump rational behaviour when discussions of reform are on the table," Manuel said.

The most relevant institution at the moment was the Group of 20 (G20), consisting of the world's 20 largest economies.

But Africa's representation in the G20 was only through South Africa and it was not clear if South Africa represented itself, Africa, or poor countries in general.

"At various times, it has shifted between all three of these roles."

The same problem arose when the Group of Eight (G8) countries met.

"Africa is invited through both the African Union [AU] and through individual countries. Again, it not clear if South Africa or Nigeria represent the continent.

"Equally, it is not clear if the AU and the institutions of the AU are mature enough to represent the myriad interests that define Africa," Manuel said.

Africa had been lagging behind the rest of the world in terms of economic growth which was not yet sustainable for poverty reduction.

"Africa needs two to three decades of rapid growth to make a substantial dent in the level of poverty."

Quoting Nancy Birdsall of the Centre for Global Development, Manuel said in Africa, 42,4% of its population lived below the bread-line in 1981. That figure remained relatively static on 41% in 2004.

Meanwhile, the number of people living below the bread-line in East Asia dropped by nine percent in the same period and by nearly 20% in South Asia.

Africa's best option was to create stronger regional and continent-wide institutions and larger trade blocs.

"Put simply, greater unity would help us punch above our weight," Manuel said.