Ambitious plans to link Switzerland's major cities with a high-speed underground railway, known as Swissmetro, appear to be dead.
Some of its main supporters are pulling out of the project and its capital has shrunk dramatically.
The kiss of death appears to have been a newspaper interview in which the Swiss transport minister, Moritz Leuenberger, said he no longer believed in the scheme.
The Employers Federation in French-speaking Switzerland is withdrawing from the project, allegedly because of the interview.
Pierre Weiss, the secretary general of Swissmetro and a member of the Employers Federation, said he would resign from the project at the end of December.
Weiss said he did not believe Swissmetro would get an operating concession at any time in the foreseeable future.
Meanwhile, the society's capital has shrunk from SFr6.7 million ($4.6 million) to just SFr340,000, with shares worth less than SFr50 - down from SFr1,000.
Swissmetro is holding an extraordinary general meeting on December 6.
"It won't become part of federal transport policy again," Michele Mossi, Swissmetro's managing director told swissinfo. "However it could develop into a programme of research and development."
Mossi said some of the key concepts of the project were still of interest to industrial partners.
"In the world of industry, there are people who are interested in the resistant cement of the gallery, the safety of the underground structure and the system of magnetic levitation in a vacuum."
Swissmetro is a magnetically-levitated high-speed system of transportation where trains would be able to achieve top speeds of 500kmh thanks to a partial vacuum in the tunnels.
Its planned route stretches from Geneva to St Gallen, via Lausanne, Bern and Zurich.
Asked about its prospects last week, Leuenberger said that, as minister of transport, he no longer believed in it.
"Even if I stayed in office for 15 years, Swissmetro would still not be sufficiently advanced to be included in transport planning," he told the newspaper, "24 Heures".
"When I see that it takes 12 years or more just to drill through the Gotthard [tunnel], I can't imagine the work that would be necessary to drill a tunnel the whole length of Switzerland."
"And when I think of the safety issues which already pose difficulties in our tunnels, I can't see how one could resolve them for Swissmetro."
As recently as two years ago, a transport ministry report on public transport raised serious doubts about the viability of the project.
Even if the project still goes ahead, researchers say the futuristic mode of transport is unlikely to be operational before 2030 at the earliest.
swissinfo with agencies