The Bishopsgate Goods Yard could be demolished as soon as next week following a ruling in the Court of Appeal against London's railway heritage lobby.
The court found that the London Boroughs of Hackney and Tower Hamlets acted correctly in giving planning permission for the demolition to make space for London Underground's extension of the East London Line.
However, conservationists warned they might take the case to the House of Lords, a move that observers say would cause serious delay to LUL's project.
Conservationist Andy Prokopp said after the ruling that he was disappointed with the court's decision but vowed to fight on.
In response, London Underground insisted that any further delays caused by court proceedings against the demolition would put the East London Line extension 'in serious jeopardy'.
Prokopp has, however, lost the support of English Heritage, which has made clear its disappointment over the loss of the Goods Yard, but has vowed to 'preserve the buildings by record'.