Which city do you think is the World's most expensive? London? Beijing? New York? None of them apparently!

The latest annual cost of living survey conducted by Mercer, the American financial services company, found that two African cities were the most expensive areas or expatriates.

The survey, which analyzes 211 cities across five continents, measured the cost of over 200 items including transportation, housing, food, household goods, clothing and entertainment in each of the location and compared the cost to the base city - New York City. All the currencies were weighed against the dollar and prices have been arrived at after considering the impact of inflation on goods and services.

The aim of the survey is to help multinational companies to chalk out remuneration plans for employees working in different corners of the world.

"While multinationals continue to recognize the importance of having a global workforce and corporate assignments remain prevalent, they must be able to monitor and balance the cost of their expatriate programs. Employers need to evaluate the impact of currency fluctuations, inflation, and political instability when sending employees on overseas assignments while ensuring they retain talented employees by offering competitive compensation packages," Ed Hannibal, Partner and Global Leader for Mercer's Mobility practice, explained in a statement.

The survey found that African, Asian and European cities were the most expensive for expatriates.

"Rankings in many regions were affected by recent world events, including economic and political upheavals, which resulted in currency fluctuations, cost inflation for goods and services, and volatility in accommodation prices," Hannibal added.

Below is the list of the top 10 most expensive cities of the world:

1.     Luanda, Angola

2.     N'Djamena, Chad

3.     Hong Kong, Hong Kong

4.     Singapore, Singapore

5.     Zurich, Switzerland

6.     Geneva, Switzerland

7.     Tokyo, Japan

8.     Bern, Switzerland

9.     Moscow, Russia

10.   Shanghai, China

However, CNBC explains that while Luanda did claim the top spot on the world's most expensive list for the second consecutive time, it is also one of the most underdeveloped cities in Africa. Sine Angola relies heavily on imports, Luanda was bound to be expensive.

"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," Hannibal said.

Meanwhile, the most expensive city in the U.S. was New York City, taking the 16th spot on the world's most expensive cities list and London was the most expensive city of the U.K. coming in 12th on the list.

Check out the complete list on Forbes and the survey report here.