In total there were 21 US markets among the world's 100 most expensive. After the top four, the priciest prime office space in the US can be found in West Palm Beach, FL, San Diego and Lower Manhattan.

"From an occupancy cost perspective, the US remains a great place to do business," points out Ward Caswell, CBRE's director of information management. "While US rents are rising, they aren't rising at the same rate as they are internationally, even when accounting for the recent appreciation of the dollar against foreign currencies."

Caswell adds that the survey also underscored the continuing recovery of US office markets. More than half of the 58 US markets surveyed recorded higher rents at mid-year 2005 than at the end of 2004, indicating that the recovery cycle has reached an inflection point in terms of pricing in many office districts.