The tallest residential building in the world, the 2,000ft high Chicago Spire, has been given planning permission.

Designed by Santiago Calatrava, the 150-floor twisted tower will be located where the Chicago river meets Lake Michigan, dramatically changing the City skyline. The developer is Shelbourne Development Group and property services company Savills will be marketing the 1,200 apartments. Work on site is expected to start next month, with completion due in 2010.