Two African cities top the list of most expensive cities for expatriates according to Mercer's 2014 Cost of Living Survey.
Although not typically recognised as wealthy cities compared to others, Luanda in Angola is the world's most expensive city for the second year in a row followed by N'Djamena, Chad.
"While Luanda and N'Djamena are relatively inexpensive cities, they are quite costly for expatriates since imported goods come at a premium. In addition, finding secure living accommodations that meet the standards of expatriates can be challenging and quite costly as well. This is generally why some African cities rank high in our survey", said Mr Ed Hannibal, Partner and Global Leader for Mercer's Mobility practice.
European and Asian cities also continue to dominate the rankings as the costliest cities with Hong Kong in third place, followed by Singapore.
Zurich jumped three places to rank fifth, followed by Geneva in sixth. Tokyo dropped four spots to rank seventh.
Karachi, ranked 211, is the world's least expensive city for expatriates. The survey found that Luanda is more than three times as costly as Karachi.
In 90th position, Birmingham has jumped forty-five places, Aberdeen (94), Glasgow (108) have risen thirty-four and forty-nine places in the rankings respectively. Belfast (120) is the UK's least expensive city, up thirty-eight places in the ranking from 2013.
"This year, UK cities have surged in the ranking, mainly as a result of a strengthening of the British pound against the US dollar. The UK's soaring housing market has also had an impact, with added pressure on the rental market as many buyers face difficulties in obtaining a mortgage," said Ellyn Karetnick, UK Head of Mercer's International Mobility Practice.
"Glasgow and Birmingham have experienced the greatest jumps as they have had significant cost-increases on goods and services, and rentals."
The Cost of Living Survey covers 211 cities across five continents and measures the comparative cost of over 200 items in each location, including housing, transportation, food, clothing, household goods, and entertainment
Currency fluctuations and the impact of inflation on goods and services have influenced the cost of expatriate programs as well as the city rankings.