Hopes that this week’s planned tube strike might be cancelled have been dashed after unions rejected an offer made on Friday by London Underground.

Unions said they were left with no choice but to take industrial action for 24 hours from Wednesday evening, spelling misery for commuters by completely closing the capital’s tube network on Thursday.



The second strike in a month was called in a dispute over terms and conditions for the introduction of 24-hour train services on weekends from September.



While unions do not oppose all-night running, they are seeking guarantees about the number of weekend night shifts drivers and other staff will be forced to work.



Finn Brennan, the London district organiser for Aslef, the drivers’ union, said it had consulted members across every line and depot: “The main concern is the complete lack of firm commitments on work-life balance for train drivers. We would be prepared to continue discussions to try to find common ground, but senior management are insistent that new rosters will be issued this week so the night tube starts on 12 September.

“This leaves us with no other choice than to go ahead with strike action from 21.30 on Wednesday. We genuinely regret the disruption this will cause.”

London Underground has said most drivers would not be required to do more than a few additional weekend night shifts.



The RMT rejected the proposed deal, warning that it had concerns over how the proposed night tube service would impact on the network and that weekday commuters could pay a heavy price in terms of safety, reliability and quality without weekend downtime. It accused the London mayor, Boris Johnson, of creating a vanity scheme “without any understanding of how the railway runs in reality”.

The union’s general secretary, Mick Cash, said RMT negotiators remained available for talks, but added: “The night tube plan has been botched from the off. The basics haven’t been done and those who will pay for this shambles will not only be our members but the London daily travelling public who cough up a fortune and will find their safety and the reliability of the service compromised from 12 September onwards.”

Manuel Cortes, the leader of the TSSA union, said it had rejected the offer not on the grounds of pay but the work-life balance of its members, as well as safety issues. He said: “There are a number of stations where there will be one member of staff on duty during the middle of the night. With crowds of potential drunks to deal with, we think that could be an accident waiting to happen.”

He said the union remained available for discussions “anywhere, at any time”. Unite, which represents a small minority of tube staff, has also dismissed the offer.

Talks at the conciliation service Acas may restart but would now appear unlikely to avert the planned strike.



Transport for London (TfL) is advising passengers to complete their journeys by 6.30pm on Wednesday and avoid travelling at peak times on Thursday if possible.

It will run extra bus and river services to help people get around, but expects all public transport and roads to be much busier than usual. Additional cycle hire docking stations will be open in central London. The DLR, London Overground, trams and national rail services will run as normal, but will be much busier.

Steve Griffiths, London Underground’s chief operating officer, said: “Our customers are advised to check the TfL website for the latest information as we seek to resolve the dispute and to keep London moving should the unions go ahead with their action.”

Nick Brown, the managing director of London Underground, blamed unions’ intransigence for the deadlock. He said staff would eventually have the option of whether or not to work weekend night tube shifts, but most were already working on rotas that covered operations over 24 hours, seven days a week, so the night tube would mean a subtle change to rosters.

Watch vintage newsreel of London tube strikes over the last 50 years Guardian

Staff have been offered an average 2% salary increase this year, and a 1% or RPI inflation rise, whichever is higher, for 2016 and 2017, as well as extra payments to drivers working night tube shifts and additional bonus payments to all affected staff once the weekend service starts operating.



Brown accused unions of holding a “gun to the head” of tube management in talks before the new service starts. He said: “The RMT has an agenda that is untenable as we try to modernise our customer service proposition for the tube.”



He said that redeployment of staff after the closures of ticket offices, which prompted previous strikes and are still contested by the RMT, had been hugely well received by the public, and no jobs had been lost through compulsory redundancies. He said London Underground remained available for talks.



In a separate dispute, RMT members at First Great Western will take renewed strike action, including a three-day stoppage over the bank holiday weekend starting on 29 August.