A spectacular new extension to Tate Modern is supposed to be the UK's most powerful cultural statement for the Olympic year of 2012.

However the new wing, planned to increase museum floor space by 60 per cent, may still be a building site when the games start, Tate director Sir Nicholas Serota has admitted.

James Purnell, the former Secretary of State for Culture, Media and Sport who announced Tate’s government grant last year, spoke then of the unique opportunity the new extension would provide to showcase UK culture during the Olympics - an opportunity that will be missed if the Bankside extension is not yet complete.

The extension, by architects Herzog and de Meuron, will cost £215m. Of that, £70m has already been raised, including £50m via a one-off grant from the government.

Source: The Guardian, July 2008