The former Portuguese colony, sub-Saharan Africa's second largest oil producer, exports nearly 2 million barrels of oil a day and has established two funds to collect oil revenues above budgeted levels: one to stabilise future spending and the other for investment projects in the non-oil sector, David said.

"We need to diversify the economy," he told a meeting of the U.N. Conference for Trade and Development (UNCTAD), noting that oil accounted for around 95 percent of Angola's exports and 50 percent of its gross domestic product.

"Our economy is still very vulnerable," he said.

David said Angola had concluded infrastructure deals with China, including a recently completed 500 megawatt hydroelectric power plant, to help rebuild the southern African country after a devastating three-decade civil war.

A second plant was in the pipeline, he said.

Inflation, meanwhile, was declining. It fell to 11 percent in 2007 and David predicted it would reach single digits this year. Economic growth hit 23 percent in 2007, he said.

"The growth rate in the non-oil sector last year was in excess of 40 percent and for the first time were higher than the growth rate from the oil industry," he told delegates.

Although Angola had previous ranked as one of the world's most important growers of cocoa and coffee, the government was more interested in industrial sectors which would bring more added value to the economy and provide more jobs, David said.

"We hope we can use the benefits of the oil industry to improve the level of human development in our country," he said.