The result of a ballot for strike action by South Yorkshire railway workers is expected later today.
Conductors on Arriva Rail North trains who are members of transport union RMT are taking action in a row over the role of guards on trains.
The union said this comes after the firm failed to provide assurances over the future of train guards. They have until the end of today to send in their ballot papers.
RMT general secretary Mick Cash said: "We asked Arriva Rail North whether they were prepared to guarantee a second person on all passenger services operated by the company and whether that second person would retain full operational responsibility, for train dispatch, platform train interface and current rule book requirements for dealing with contingency arrangements, such as evacuation and protection of the train.
“The response from the company was ‘we are not in a position to offer either of these guarantees’."
A spokesman for Northern Rail called the ballot for action 'premature.'