Thousands of rail workers have been left "dangling by a string" because of unanswered questions over the future of the East Coast mainline, a union has warned.
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The Rail, Maritime and Transport (RMT) union said there were key operational issues over what happens next after Transport Secretary Chris Graying announced that Stagecoach would continue running the London to Edinburgh line only for a few months while the government may step in to run the service.
The Department for Transport (DfT) said the move would not affect services or workers.
RMT general secretary Mick Cash said: "On Monday Chris Grayling told the Commons that Virgin/Stagecoach would be allowed to lurch on for a few more months on the East Coast, staff would notice no difference and that all options for the future, including the public-sector option, were under consideration.
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"Since then he has not come forward with a shred of detail as to what happens next and what his operational plans actually are.
"That leaves thousands of rail workers caught in the crossfire of the privatised chaos on this crucial route in the dark as to what the future holds and RMT will not allow those responsible to drop this bombshell and then run for cover.
"No-one from the DfT has had the common decency to pick up the phone to the union and we will not allow our members to be treated as collateral damage in this third, privatised failure on the East Coast.
"There are RMT members on the job today who have gone from British Rail, to GNER, to National Express, to Directly Operated Railways, to Virgin/Stagecoach, and who are now left wondering who their sixth employer will be in little more than two decades on this vital section of Britain's rail network.
"That is a shameful way to treat the workforce and shines the spotlight on the continuing chaos of rail privatisation."
Mr Cash said rail workers had been left "dangling by a string" because of the "shambles".