The London Underground could once again be affected by strikes as the UK's biggest rail union announced plans to ballot workers over projected job losses.
According to the RMT, around 3,800 station-based workers are involved in an "ongoing battle" over jobs in connection with the dispute over the closure of manned ticket offices.
The union said nearly 900 jobs will be lost at stations while passenger figures keep increasing.
RMT General secretary Mick Cash said: "London Underground knows that it has compromised safety and customer service across its stations by cutting jobs.
"A responsible employer would reverse the job cuts and put staff back into station control rooms. If London Underground really cares about passengers it would reverse the ticket office closure programme.
"The continuing impact of those cuts leaves us with no alternative but to move to a ballot for industrial action.
Mr Cash added that in addition to staff reductions at stations, jobs have been cut from underground control rooms compromising safety standards.
TfL have responded to RMT's comment by stating the safety of staff and customers are a "top priority".
Steve Griffiths, London Underground's Chief Operating Officer, said: "The safety of customers and staff is our top priority and our hardworking people ensure London Underground remains one of the safest metros in the world.
"There are more of our staff available to customers in public areas of stations than ever before and crime is at its lowest ever level.
“As the Mayor announced last month, an independent review into the ticket offices is being carried out by London TravelWatch to ensure that it's delivering for our customers."
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