UNITED NATIONS - The world has made strong and sustained progress in its fight against poverty, but still faces new challenges such as higher oil and food prices and the global economic slowdown, a new UN report said Thursday. Since 2002, rising prices for mineral and agricultural raw materials have contributed to the remarkable run of economic growth in all developing regions, according to the UN's Millennium Development Goals Report 2008. However, many developing countries are now facing higher import bills for food and fuel, jeopardizing their growth, the report said. It noted that improved estimates of poverty from the World Bank showed that the number of poor in the developing world is larger than previously thought, at 1.4 billion people. But the new estimates confirmed that between 1990 and 2005, the number of people living in extreme poverty has fallen -- from 1.8 to 1.4 billion -- and that the 1990 global poverty rate is likely to be halved by 2015. Most of the decline, however, occurred in East Asia, particularly China, other regions had much smaller decreases in the poverty rate and only modest falls in the number of poor. Sub-Saharan Africa and the former Soviet republics actually saw the number of poor increase between 1990 and 2005. In a reversal of this previous global downward trend, the prevailing higher food prices are expected to push many people into poverty, especially in sub-Saharan Africa and Southern Asia, already the regions with the largest numbers of people living in extreme poverty, the report said. The UN's Millennium Development Goals Report 2008 is the most comprehensive global assessment to date on progress towards the targets, which range from eradicating extreme poverty and hunger, and achieving universal primary education, to reducing child mortality and combating HIV/AIDS, malaria and other diseases. It was released ahead of the UN High-level Event on the Millennium Development Goals scheduled for Sept. 25, to be convened by UN Secretary-General Ban Ki-moon and the incoming President of the General Assembly Miguel D'Escoto Brockmann. Representatives from some 150 countries, including more than 90 heads of state or government, are expected to attend the event to review progress to date, identify gaps and commit to concrete steps to ensure that all countries can achieve the MDGs.