World's Most Expensive City to Rent Is...

Hong Kong financial district.
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Asia's financial capital Hong Kong retained its top spot as the world's most expensive city to rent a high-end apartment as robust demand on the island, a popular destination for employees looking to relocate overseas, and constrained supply, kept prices elevated.

Rents for an unfurnished 3-bedroom apartment in a sought-after area of Hong Kong averaged $11,500 per month in 2012 – down 2-3 percent from a year earlier – but over 3 times the regional average of $3,640, a survey by consulting firm ECA International published on Tuesday showed.

"High demand and limited space have kept up rents for high-end property in Hong Kong for some time now, and that remains the case," said Lee Quane, regional manager, ECA International, Asia.

(Read More: Hong Kong Property Curbs Have Some 'Unintended' Victims)

"Nevertheless, we have observed fluctuations as confidence in the financial sector – the source of a good deal of demand for high-end properties – ebbs and flows due to uncertainty in the euro zone. The rise and fall in expatriate numbers as a whole also contributes to fluctuations," Quane added.

The territory is followed by Caracas, Venezuela's capital city, where demand, driven by a booming petroleum industry, is fueling a steep rise in rents.

Global financial hubs New York, Moscow and Tokyo ranked third, fourth and fifth most expensive cities for rents respectively.

Overall, on a global level, average monthly rents edged lower to $3,080 in 2012, compared with $3,030 in the previous year – a reflection of uncertainty over the global economic outlook, ECA said.

(Read More: Property Investors Keen on US, Turkey; China Stumbles)

Tokyo saw a notable fall in accommodation prices, with rents for high-end apartments declining 5 percent from a year ago.

"Falling demand as many international companies scale back their operations in Japan to reduce costs has lowered the pressure on availability and thereby rental prices," Quane said.

Bucking the downtrend, however, was Asia's largest economy China. Despite the economic slowdown in the mainland and measures introduced by the government to curb speculative demand in the real estate market, rents in Beijing, for example, increased 12 percent year-on-year.

This was largely a result of foreign companies looking to expand their operations in the country, ECA reported.

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Asia-Pacific cities on the whole dominated the top 20 ranking, with Singapore, Shanghai and Seoul, coming in 8th, 11th and 14th place, respectively.

"With more and more companies setting up operations in the region, the need for the type of housing appropriate for international assignees has increased. Yet with an already limited supply of such properties in many countries here, demand significantly exceeds supply, putting upward pressure on rents," Quane.