Major tube strikes are expected to affect the entire London Underground network this week.
The RMT union confirmed on Friday that talks with arbitration service Acas had broken down.
As a result, Transport for London (TfL) staff will stage mass walk outs on two days.
The dispute is over jobs, pensions and working conditions.
Among other things, London Underground staff are protesting major staff cuts announced in December as part of a wider TfL plan to save money.
Some 500 jobs are set to be axed across the network, with many of the larger stations bearing the brunt of the cuts.
Early in February, the RMT union instructed members to stop work on Tuesday 1 and Thursday 3 March.
The union says more than 10,000 members working on the Tube were invited to take part in a ballot. Of those who responded, 94 per cent voted to strike – though this is understood to be less than half the number of union members on the Underground.
Earlier this month, RMT general secretary Mick Lynch said: “Our members will be taking strike action next month because a financial crisis at LUL has been deliberately engineered by the Government to drive a cuts’ agenda which would savage jobs, services, safety and threaten their working conditions and pensions.
“These are the very same transport staff praised as heroes for carrying London through Covid for nearly two years, often at serious personal risk, who now have no option but to strike to defend their livelihoods.”
TfL has condemned the strike call. Chief operating officer Andy Lord said: “It is extremely disappointing that the RMT has today announced strike action, as no proposals have been tabled on pensions or terms and conditions, and nobody has or will lose their jobs as a result of the proposals we have set out.”
TfL has repeatedly issued warnings that it will be forced to begin a “managed decline” of London’s public transport network unless it secures a multi-year funding deal to replace fares revenue lost during the coronavirus pandemic.