A property developer is suing Ealing Council for more than £2.5 million alleging the authority failed to declare a site it bought was safeguarded for Crossrail.
Neptune Property Developments plans to take the council to court after buying 267 Horn Lane, Acton, and was unable to develop because it had been set aside for a new ticket hall.
Neptune is reported to have bought the land for £800,000 in September 2006 with the aim of building 14 two-bed apartments at the site.
The privately-owned developer claims its solicitors asked Ealing officials to carry out a search of the register of local land charges before agreeing to buy the land.
In its claim to the High Court, Neptune alleges Ealing failed to inform it the property was subject to a safeguarding direction.
The firm is claiming the millions in lost cash, including the site cost, expected profit various fees and continued interest payments in the debt required to buy the site of £3,950 a month.
Patrick Heffron, Neptune Group director, said: "In the course of buying the property we relied, as one does, on a local search from Ealing Council, which was totally clear.
"Later and only when planning consent was refused, did we find out that Ealing had totally failed to register the local land charge against the land which should have been registered. We have now issued proceedings as the council is liable under statute for its omission."
Ealing has referred the matter to its insurers who are investigating.