An MP has issued an ultimatum after delays were announced to a planned train service between Cleethorpes and London.
Train operator LNER had hoped to introduce the route through Grimsby, Lincoln and Market Rasen to the capital in December.
However, the firm said there were "infrastructure issues that need to be resolved" before it could begin operations.
Edward Leigh, MP for Gainsborough in Lincolnshire, told the Commons he would "lie down on the line" to stop the train if it failed to stop at Market Rasen - in his constituency.
Local MPs have been campaigning for the return of the service for decades.
Speaking in the Commons on Thursday, Sir Edward said the previous minister had promised him, and the member for Brigg and Immingham, Martin Vickers, that he had instructed LNER and Network Rail "to ensure that we get our through train from Grimsby to London".
Addressing roads minister Lilian Greenwood, Sir Edward asked: "Will the minister confirm that she will continue those firm instructions and, above all, ensure that this train stops?
"If it does not stop in Market Rasen, I am going to lie down on the line and stop it that way," the MP added.
In response, the minister said: "I do hope the right honourable member will not put himself in such danger.
"We are working with industry to address issues that need to be resolved."
Last year, test runs were carried out to check whether the direct daily train service to London could be reinstated.
Rail magazine has reported there were issues with Market Rasen station because it has no footbridge or subway.
The publication's acting news editor, Andy Comfort, told BBC Radio Humberside: "No through train from Cleethorpes to London in December and I'm afraid not for the foreseeable future."
In a statement, LNER said: "The industry is working to address timetabling, financial, operation and infrastructure issues before any service to Cleethorpes could be introduced."
The BBC has contacted the Department for Transport for a response.
No new date has been given for when the service could start.
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