Pretoria - African powers Angola, Nigeria and South Africa on Friday endorsed the nomination of Nigerian Finance Minister Ngozi Okonjo-Iweala, a respected economist and diplomat, as a candidate to take over the World Bank. The United States faces an unprecedented challenge to its grip on the World Bank presidency, with emerging economies poised to nominate at least one candidate on Friday to set up the first contested bid for the top job at the global development lender. “The endorsement is in line with the belief that the appointment of the leadership of the World Bank and its sister institution, the International Monetary Fund, should be merit-based, open and transparent,” the three said.South Africa chairs one of the three African seats on the 25-member World Bank board, and earlier this week sources said Okonjo-Iweala’s candidacy was being proposed after consultations between President Jacob Zuma and Nigeria’s President Goodluck Jonathan. The joint endorsement is a rare bit of unity among the three countries often at loggerheads as they battle for dominance on the continent. “She has eminent academic qualifications and would be, I think, a candidate of choice not only on the African continent but well beyond as well,” Finance Minister Pravin Gordhan told a media briefing on Friday. The three countries will lobby other African states to endorse her, Gordhan added. Former Colombian finance minister Jose Antonio Ocampo is also expected to run for the post, sources told Reuters this week. Brazil said this week that both Okonjo-Iweala and Ocampo would be “great” candidates to replace Robert Zoellick as head of the Washington-based development institution, the latest sign of emerging nations wanting more say in how it is run. Washington has held the presidency since the bank’s founding after World War Two, while a European has always led its sister organisation, the International Monetary Fund.