by Miral Fahmy

SINGAPORE - Moving to Japan? It had better be on a good salary, with a global survey naming Tokyo and Osaka as the world's most expensive cities for expatriates, largely due to the strength of the yen against the US dollar.

The 2009 Cost of Living survey, by consultancy firm Mercer, covered 143 cities across the world, measuring the comparative cost of over 200 items, including housing, transport, food, clothing, entertainment and household goods.

Tokyo, last year's second most expensive city, climbed to the top spot, knocking Moscow down to number 3. Geneva and Hong Kong ranked 4th and 5th, with Asian and European cities dominating the top 10 slots.

The survey, conducted in March, uses New York as the base city for the index, with currency moves measured against the dollar. New York itself jumped to 8th from 22nd last year.

'As a direct impact of the economic downturn over the last year, we have observed significant fluctuations in most of the world's currencies, which have had a profound impact on this year's rankings,' Nathalie Constantin-Metral, a senior researcher at Mercer, said in a statement on the firm's website (www.mercer.com/costofliving)

'Now that cost containment and reduction is at the top of most company agendas, keeping track of the change in factors that dictate expatriate cost of living is essential,' she added.

Tel Aviv ranked as the most expensive city in the Middle East, while Caracas was top in South America, and Sydney was the priciest city for expatriates in the Pacific.

And the cheapest city? ... Johannesburg, which replaced Asuncion in Paraguay.

Following are the top-10 most expensive cities, according to the Mercer survey.

Last year's rankings in brackets:

1. Tokyo (2)
2. Osaka (11)
3. Moscow (1)
4. Geneva (8)
5. Hong Kong (6)
6. Zurich (9)
7. Copenhagen (7)
8. New York City (22)
9. Beijing (20)
10. Singapore (13)