Luanda, the capital of Angola in Southern Africa, has overtaken Tokyo as the world's most expensive city to live in for expatriates, according to Mercer's latest annual cost of living survey.
The oil-rich nation, which struggles with high costs of accommodation and imported goods, is back at the top of the rankings after falling into second place last year, a 2013 survey by the human resources firm showed on Tuesday. Luanda topped the list in 2010, and again in 2011.
Europe and the Asia-Pacific region were tied for the number of cities among the top 10 costliest, at four each.
Moscow was the highest-ranked European city in second place, followed by the three Swiss cities of Geneva, Zurich and Bern, which were placed seventh, eighth and ninth, respectively.
The most expensive Asian city is Tokyo, Japan, coming in third this year after placing first in 2012.
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The survey covers 214 cities around the world and measures the cost of over 200 items in each place in March such as housing, transportation, food and clothing, using New York as a the base city.
Angola, which is Africa's second largest oil producer after Nigeria, attracts large multinational firms to set up base there.
But finding appropriate expat housing is one of the biggest expenses that employers face, Barb Marder, senior partner and global mobility practice leader at Mercer said in a media release.
(Slideshow: The world's most expensive places to live 2012)
"Despite being one of Africa's major oil producers, Angola is a relatively poor country yet expensive for expatriates since imported goods can be costly," Marder said. 'In addition, finding secure living accommodations that meet the standards of expatriates can be challenging and quite costly."
Last year, the average monthly rent for a luxury two-bedroom apartment in Luanda was $6,500, according to Mercer, just about $500 less than the cost in Hong Kong - which considered one of the world's most expensive real estate markets.