Docklands Light Railway link from Stratford to the Olympic Park will run 27 trains an hour during the Games
The Department of Transport has given planning approval for a Docklands Light Railway link from Stratford International to the 2012 Olympic Park.
Construction on the 3.7-mile link between Royal Victoria and the Stratford International station will start in January. The work is expected to be completed by 2010.
Mayor Ken Livingstone said the line would "provide a lasting legacy for London, bringing much-needed regeneration to the areas along the route".
The extension will involve the conversion of part of the mainline North London Line to DLR operation.
During the Games up to 27 trains an hour will run on the line.