London Undergound staff will hold three 24 hour strikes over the next month over plans for the 'Night Tube'.
Members of the RMT, Unite and Aslef unions will walk out on the evenings of 25 January, 15 February and 17 February.
It comes after the unions rejected a new four-year pay deal and pledges to hire part-time staff for the all-night weekend service.
Business leaders have blasted the decision, saying it will bring "transport chaos" back to London.
James Sproule, director of policy at the Institute of Directors (IoD), said: “Business leaders and ordinary workers in London will be shaking their heads in disbelief that they are facing yet more public transport chaos. Instead of getting on with putting their business plans for 2016 into action, our members now have to worry about how their staff are going to get into work on the three days of industrial action. In a dynamic metropolis like London, which relies on millions of workers being able to travel into the city every day, these stoppages are completely unacceptable."
Aslef London district organiser, Finn Brennan, said: "We genuinely regret the inconvenience that will be caused but the behaviour of London Underground's senior management team have left us with no other choice."
Mr Sproule added: “It is just not reasonable to subject commuters and business to the threat of ongoing strikes. The Trade Union Bill, currently being debated in Parliament, will mean that strike ballots are only valid for four months. For beleaguered Londoners, this change can’t come soon enough.”
London Mayor Boris Johnson said: "If a strike goes ahead, it will hit many London Underground workers who do not necessarily support the action, and it will cost the strikers in lost pay."
London Undergroun chief operating officer, Steve Griffiths said: "The truth is that they expect our customers to pay for their excessive demands for even more money, fewer hours and a four-day week."
"No employer could allow this and strike action will change nothing. There is no more money."
RMT general secretary Mick Cash said the union supports the idea of "properly worked-out night Tube service..[but] abject failure to work through the detail has led to a comprehensive breakdown in the negotiations".