United Nations: India and China will witness unprecedented increase in their urban populations in the next four decades, posing new challenges of providing jobs, energy housing and infrastructure to their people, a UN report said.

The UN's '2011 Revision of the World Urbanisation Prospects' said Africa and Asia will lead the global urban population growth in the next four decades with the largest increases expected in India, China, Nigeria, US and Indonesia.

India will add another 497 million to its urban population within year 2010 to 2050, while China will see 341 million people moving into urban cities followed by Nigeria (200 million), the US (103 million) and Indonesia (92 million).

The projected increase in urban population in India and Nigeria between 2010 and 2050 will be higher than that of the past 40 years.

This trend is particularly prominent in Nigeria, where its urban population grew by only 65 million between 1970 and 2010, but is projected to increase by 200 million between 2010 and 2050 -- the third largest increase in urban population of all countries of the world.

Africa's urban population will increase from 414 million to over 1.2 billion by 2050 while that of Asia will soar from 1.9 billion to 3.3 billion.

The UN said both regions would together account for 86 percent of all increase in the world's urban population.

"This unprecedented increase in urban population will provide new opportunities to improve education and public services in Africa and Asia, as more concentrated populations become easier to reach," a UN release said on Thursday.

However, it warned that the trend would also "pose new challenges of providing urban jobs, housing, energy and infrastructure to mitigate urban poverty, expansion of slums and deterioration of the urban environment".

(Agencies)