London has slipped from its perch as the world's most expensive city for offices, overtaken by Hong Kong and Tokyo for the first time in nine years.

Falling rents in the capital and a plunging pound brought occupancy costs for prime West End offices down 23% to €1403 (£1238) a square metre in 2008, property broker Cushman & Wakefield said in a report today. That compares with €1743 in Hong Kong and €1649 in Tokyo.

"The fall in rents and weak UK currency mean that for overseas companies, London is now more affordable than it has been in years," Cushman said.

London is not alone in seeing lower rental prices. The global financial crisis has pushed them lower in 16% of the world's biggest cities as financial companies fired workers and cut back on the space they lease, Cushman said.

Costs fell 4% in Hong Kong and 19% in Tokyo against a year earlier.

"There seems little doubt that rents will continue to fall over 2009, perhaps at a faster rate than before," said John Siu, general manager of Cushman & Wakefield Hong Kong.

The firm, which surveyed 202 locations in 57 countries, said rental prices climbed 3% globally, the smallest increase since 2004.

Moscow, Dubai, Mumbai, Paris, Damascus, Singapore and midtown Manhattan were the next most expensive locations for offices. Dublin fell to 15th, putting it out of the top 10 for the first time in three years.