The United Nations on Tuesday called for 'truly integrated' strategies to tackle the twin challenges of climate change and development. Addressing climate change requires investing in low-emission, high-growth strategies for developing countries, the world body said in its latest report, The World Economic and Social Survey 2009. The climate challenge cannot be met through 'ad hoc and incremental action,' it said. Instead, it requires 'much stronger efforts' by developed countries to cut their emissions. 'However, even if advanced countries begin to match their words with deeds, their efforts are, by themselves, unlikely to be sufficient to meet the climate challenge,' said the report by the UN Department of Economic and Social Affairs. According to the report, active participation of all countries in tackling the climate challenge will only come about if developing countries can maintain rapid economic growth. The technologies that would allow developing countries to make the switch to a sustainable development path presently do exist. But they are often prohibitively expensive and such a transformation would require 'a level of international support and solidarity rarely mustered outside a wartime setting,' it said. The report said that developing countries are facing 'vastly more daunting challenges than those confronting developed countries and in a far more constrained environment.' Economic growth remains a priority for them, not only to reduce poverty but also to bring about a gradual narrowing of the huge income differentials with wealthy countries, it said. 'The idea of freezing the current level of global inequality over the next half century or more is economically, politically and ethically unacceptable,' the report stated. UN Secretary-general Ban Ki-moon, writing in the report's preface, said that the survey 'makes the case for meeting both the climate challenge and the development challenge by recognizing the links between the two and proceeding along low- emissions, high- growth pathways.' 