A flagship Greenwich Sainsbury's store will not be listed - leaving the way open for it to be knocked down and replaced with an Ikea.
The Twentieth Century Society had applied for the peninsula supermarket, once praised for its sustainable credentials, to be made a listed building and protected from demolition.
But English Heritage turned down the application, granting it immunity from designation for five years.
Society senior conservation adviser Henrietta Billings said: "We are deeply disappointed with the decision not to list the Sainsbury’s millennium store.
"It was the most innovative supermarket building to have been built in the last 50 years, and it was in our view, the best and most obvious candidate for listing. This is just the type of retail architecture we should be celebrating and not demolishing."
The store is due to be demolished and replaced with a massive new Ikea in a project approved by Greenwich Council's planning board despite a community campaign.