Workers on CrossCountry Trains are to be balloted for strikes after union leaders said there had been a "comprehensive breakdown" in industrial relations.
Train managers, conductors and on-board catering staff at the operator which links Oxford and Banbury with the South coast, Midlands and the north of England will vote in the next few weeks on whether to launch a campaign of industrial action.
The Rail Maritime and Transport union said there were a number of issues involved in the dispute, including rosters, training, pay, and the dismissal of a union health and safety rep.
General secretary Bob Crow said: "As a result of the total collapse of industrial relations across a whole raft of matters, RMT has now informed CrossCountry that a dispute now exists between our two organisations and that we will remain in dispute until all these issues are resolved to our satisfaction."
CrossCountry spokesman Richard Gibson said: “We are aware the RMT Union are balloting their members at CrossCountry.
“We are continuing to discuss the matters they have raised on behalf of their members and are hopeful their concerns can be resolved.”
The ballot will close on December 11.