Members of the RMT have described the plans, that could put stations across Thameslink, Southern and Great Northern under threat, as ticket office carnage. The news comes on the back of the unions plan to stage a 48-hour strike on the London Underground this weekend in a long-running dispute over jobs. Members plan to walk out on Saturday at 9pm, which means the action will undoubtedly cause problems from commuters travelling in London on Monday. London mayor Boris Johnson has described the intended action as totally unnecessary. The RMT says it will campaign to defend jobs and services as it emerged that 81 stations are part of a formal public consultation, which could see some ticket offices closed immediately, some will close after passengers have been shown how to use ticket machines and others will close outside peak hours. RMT general secretary Mick Cash said: These plans, driven by the desire to de-staff our railways in the quest for profit, would unleash a wave of ticket office carnage across rail franchises that are already seen as the basket-cases of Britains privatised railway network. A spokesman for train operator, Govia Thameslink Railway, said: We want to modernise the way we operate approximately 80 of our busier stations for the benefit of passengers, many of whom now buy their tickets online, or use Oyster, contactless and smartcards. Where sales from ticket offices are low, we want to bring staff from behind the windows and on to the concourse to work where theyre needed most, as station hosts, providing assistance and helping to sell tickets from ticket machines and their own handheld devices. The spokesman confirmed that no ticket offices would close immediately and pointed out that the proposals had yet to go through a public consultation process and would also be discussed with London TravelWatch and Transport Focus and then require approval from the Department for Transport. We are also speaking to our trades unions about this. There will be no compulsory redundancies as a result of our plans, the spokesman added Huntingdon and St Neots ticket offices being considered under the heading of proposed closure outside of peak hours.