The RMT's London Underground members will be taking industrial action from Tuesday 7 March, but Transport for London (TfL) has said the action - which is short of a strike, shouldn't cause disruption to services.
That's unless it continues to drag on of course.
The dispute is over a "breakdown in industrial relations" according to the union, after a recent ballot recorded 67 per cent of those voting in favour of strike action and 88 per cent voting in favour of action short of a strike. The ballot had a 43 per cent turnout.
Its fleet members have been instructed to begin a work-to-rule from 00:01 on Tuesday "until further notice".
Instances where they've been told not to work include:
- Not working any overtime or attending training courses outside of normal working hours
- Not to carry out any higher grade duty work
- Not to change any shifts or work locations to assist with maintenance
- No trainers should carry out training for anyone on a job that is not their substantive role
- No coaches to coach anyone on a job that is not their substantive role
- Not to work if there is no first aider on site
RMT general secretary Mick Cash said: "The continued failures by the management side have left us with no option but to begin a campaign of industrial action."
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“RMT’s position could not be clearer and it is down to London Underground to start taking this list of grievances seriously, to stop trying to impose fundamental changes to agreed policies and working conditions and to halt the bullying and harassment of our reps. RMT remains available for serious talks," he added.
A TfL spokesperson said: “We urge the RMT leadership to work with us constructively on the issues it has raised rather than threaten unnecessary industrial action.”
It marks the latest London Underground industrial action after the RMT held a walkout affecting the Central and Waterloo & City Lines last month. That was over a separate dispute regarding the displacement of eight drivers from their home depots to others in central London.
A massive strike in January brought chaos to the capital after the majority of Zone 1 stations were closed, in a row over safety and staffing issues.