World cities, home to most people, to add 2.5 billion more by 2050 - U.N.

Pedestrians walk at a scramble crossing at Shibuya shopping district in Tokyo in this February 28, 2014, file photo. REUTERS/Yuya Shino/Files

UNITED NATIONS (Reuters) - More than half of the world's seven billion people live in urban areas, with the top "mega cities" - with more than 10 million inhabitants - being Tokyo, Delhi, Shanghai, Mexico City and Sao Paulo, according to a United Nations report on Thursday.

That proportion is expected to jump, so that more than six billion people will be city dwellers by 2045, the UN's World Urbanization Prospects report said.