Office rental growth in Tokyo may slip below 10 percent in 2008 for the first time in four years as the economy slows, cutting corporate spending, real estate brokers said.

Rental growth for so-called Grade A office buildings in Tokyo in 2008 will be less than half of last year's 16 percent, said Takeshi Akagi, head of research at Jones Lang LaSalle Inc. in Tokyo. CB Richard Ellis Group Inc., the world's largest commercial real estate broker, expects 8 percent to 10 percent growth for new Tokyo lettings, down from 19 percent in 2007.

"The property cycle is maturing, and on top of that you have the economic cycle slowing," said Christian Bernasconi, managing partner of B&I Capital AG. "Rental increases will be less rapid in the next two years."