High speed commuter services for Kent on the Channel Tunnel Rail Link may never happen, according to a senior rail official.
Thanet and the Medway towns may miss out on regeneration
The county was promised fast domestic links to London and the Continent as one of the advantages to counter the disruption caused by the project.
But Jim Steer, managing director of the Strategic Rail Authority, has told BBC Radio Kent that commuters may lose out.
He said: "The worst case scenario, I suppose, would be under a lot of spending constraints the prospect that there would be no domestic service at all on the Channel Tunnel Rail Link.
Severe funding constraint
"That's something we hope wouldn't happen, but if there was a very, very severe national constraint on funding for rail, then I would have to say that that's a conceivable outcome."
Mr Steer said he was confident that some high speed trains would serve the county, however.
Kent commuters have less than a week to add their voice to government consultation on where the service should stop in the county.
The favoured candidates for high speed links include Gravesend, Ashford and Canterbury stations.
Funding constraints may mean high speed trains do not stop in Kent
But Thanet and the Medway towns seem likely to lose out because of the additional costs involved.
Medway Council sent staff out on roller skates earlier this month to try to rally support from rail users at Rainham, Gillingham, Chatham and Rochester stations.
The council argues an improved service is vital to open up commercial and employment opportunities for the area.
Regeneration for large areas of Kent and London was promised when the rail link was first put forward.
The National Audit Office, a national spending watchdog, has also confirmed to the BBC that the taxpayer could be exposed to more than £9bn in loans and other guarantees to get the link completed.
Successive governments have always claimed the financial risk lay with the private sector.
But the government has already had to bail out developer London and Continental Railways on more than one occasion - and the taxpayer may foot the bill for more liabilities in the future.
London and Continental won the Private Finance Initiative contract to build the £3bn, 67-mile rail link between London and the Channel Tunnel, and operate Eurostar, in 1996.