Swiss architects Herzog & de Meuron have revealed plans for their £215 million iconic extension to the former power station on the south bank of the River Thames. The new 7,000 m² extension will be built on land to the south of the Tate Modern reclaimed from EDF energy networks. A new entrance and piazza to the 4 million visitor/year venue will allow north-south pedestrian passage through the complex. Ten new galleries will be provided in the 10 stories above ground and a performing space will be created within the former oil tanks, once used to feed the power station located below ground. The Mayor of London today pledged £7 million pounds towards the project through the London Development Agency. Completion is scheduled for 2012.