GENEVA (AFP) - A UN agency on Thursday called on the worlds poorest countries to seize the financial crisis as an opportunity to reform chronically frail economies, days after Barack Obama urged Africans to demand change. The UN Conference on Trade and Development (UNCTAD) warned the 49 least developed countries (LDC) 33 of them in Africa that they had reached a turning point as the crisis wiped out nearly two-thirds of their growth. Business as usual is no longer possible, said UNCTAD economist Charles Gore. The crisis has exposed more than ever the shortcoming of development paradigm and least developed countries should seize the crisis as an opportunity for change, he told journalists. An annual report by UNCTAD underlined that the poorest nations faced the combined blow of falling commodity prices, a drop in private investment, and declining remittances from migrants abroad, on top of the lingering impact of food and energy crises last year. The combination of high exposure to shocks as well as weak resilience to those shocks is likely to mean that the LDCs, which already face chronic development challenges, will be harder hit than most. Gore cited UN forecasts indicating that the combined growth rate of the Least Developed Countries would fall to 2.7 percent this year, against an annual average of 7.4 percent between 2003 and 2007. The UNCTAD report called for wholesale state-led reform in the poorest nations to decrease their reliance on commodities, implement sweeping changes to agriculture, and increase their own productive capacities to serve young populations. But it also urged them to embrace a new approach based on good governance, where the state focused its political and administrative resources on broad-based economic development. These measures will not only help to mitigate the impact of crisis and shorten its duration but also to ensure that development after the crisis will be more resilient and more inclusive, said Gore. US President Barack Obamas condemnation of Africas corrupt big men at the weekend resonated across the continent, stirring a chorus of calls for better governance. In a speech in Ghana, Obama said there was a need to redefine donors aid relationship with Africa. But he insisted that broader investment and trade would require nations across the continent to build more solid institutions.