Hong Kong
Hong Kong tops the annual chart by Mercer as the most expensive city in the world for international workersLo Ka Fai/China Photos/Getty Images

Hong Kong tops the list of most expensive cities for those working abroad surpassing Angolan capital Luanda, according to a global survey released by consultancy firm Mercer. Luanda has long been expensive for expats because of the oil boom that drew people from different parts of the world to the city. It has been pushed to the second place owing to decline in its currency value.

The 2016 Cost of Living Survey ranks 299 cities across the globe by weighing the cost in each city of over 200 items, including housing, food, transport, clothing and entertainment.

Zurich and Singapore retain their ranking from 2015 as the third and fourth most expensive cities, respectively. Tokyo has moved up six places and is now in the fifth place, while the Republic of Congo's capital Kinshasa ranked sixth and appears on the top 10 for the first time.

London has slipped to the 17th place from 12th last year, owing to the uncertainty over the EU referendum and a weaker pound. It is now a somewhat affordable and reasonably priced city for foreign workers to live in, compared to New York, Beijing, Singapore, Zurich or Tokyo.

The impact of the weaker currency is not reflected only in London. Birmingham and Glasgow have also slipped by 16 and 10 places respectively to 96th and 119th.

"While most Western European cities have remained stable in this year's rankings, UK cities have fallen," said Kate Fitzpatrick of Mercer. "However, the drop is not as large as to be expected, with steep rental prices keeping UK cities up," the Telegraph reported.

According to Mercer, renting an accommodation is one of the main factors in determining costs, as it should be of "international standards" and located in "an appropriate neighbourhood". The research estimated a two-bedroom flat in London at approximately £3,200 per month when compared with £4,754 in Hong Kong or £2,400 in Beijing.

Ellyn Karetnick, the head of international mobility practice at Mercer, said: "Although the value of the euro has remained steady against the US dollar, the pound has fallen, largely due to Brexit fears. But while currency fluctuations will always cause a major impact on costs, local conditions such as high property prices can counterbalance the impact of currency movements."