http://unstats.un.org/unsd/geoinfo/geonames/
"Through the web, database users can access short and full names of countries (193 UN member states), their capitals, and the major cities (population over 100,000) for many countries. Authoritative city endonyms are provided mainly by national name authorities and sound files are being added to assist users with pronunciation. At this stage, the database contains over 2,700 country names, some 5,700 names for 3,143 cities ..."
www.upu.int/en/resources/postcodes/addressing-systems.html