Update: All four unions have now confirmed the 24-hour Tube strike, over a dispute regarding the Night Tube, will go ahead this week.
The strike will take place from 6:30pm on Wednesday 5 August. There will be no Tube at all on Thursday. A normal service is expected to return on Friday. This is on top of existing action, including a ban on working overtime, that has been running for several weeks.
The Night Tube is due to open on 12 September, although London mayor Boris Johnson has admitted it could now miss the deadline. While TfL bosses have insisted staff will not have to work longer hours as a result, unions are up in arms about the “work-life balance”.
Unite was the first union to reject the pay deal. A spokesman for the union told City A.M: "The latest offer is effectively just previous offers repackaged.
"There are not sufficient guarantees about flexible working for the future - around the work-life balance and unsociable hours. This is just something that is being dressed up as new, but it doesn't go far enough to meet our concerns."
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Aslef followed suit this afternoon, saying the offer was "not acceptable", and criticising transport bosses for failing to give guarantees around longer term working conditions under the new Night Tube. "Vague phrases like "will seek to mitigate" and "will explore" are simply unconvincing," the union said.
"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 that Night Tube starts on September 12. The sensible option would be to postpone the launch date to allow for an agreed way forward to be reached. But once again, management are being completely inflexible and are refusing to negotiate on their offer. They are insisting that it must be accepted as it stands."
As result, Aslef had "no other choice" but to go ahead with the strike. "We genuinely regret the disruption this will cause. But the blame for this must rest with the pig headed determination of the mayor to insist on a September launch, instead of allowing more time for a negotiated settlement to be reached."
Shortly afterwards RMT's general secretary Mick Cash said: “Our members have made it clear that the latest offer from London Underground is merely a rehash of the previous package and does nothing to tackle the core issue which revolves around staff being at the beck and call of management to be hauled in during their free time to try and plug the staffing gaps which riddle the mayor’s Night Tube vanity project...
"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 who will find their safety and the reliability of the service compromised from 12 September onwards.
He added that RMT was available for talks "regardless of the point we have reached in the dispute".
This will be the second strike in a month. Business leaders have warned it could result in more than just a collective commuter headache, claiming London's economy could lose out on "millions".
The DLR, London Overground, tram and rail services will run as normal, and an extra 250 buses will be deployed throughout London, although TfL has warned they will be busier than usual.
Steve Griffiths, chief operating officer for London Underground, said:
After listening to the unions, we put forward an extremely fair revised offer, which addresses their concerns over work life balance and rewards our people for the hard work they do in keeping London working and growing.Despite this, the new offer has been rejected outright by the union leadership, again without consulting their members. We continue to urge them to put the new offer to their members and not subject Londoners to further unnecessary disruption. We remain available for talks at any time.