Tube workers are set to walk out for two full days in March as part of a union dispute over planned job cuts.
London Underground staff have been told not to work on Tuesday, March 1 and Thursday, March 3 by the union RMT.
Transport for London (TfL) said the strike action was “disappointing” and urged RMT to call off the strike.
The dispute is over TfL’s plans to cut 600 jobs as a cost-cutting measure, as well as other concerns about pensions and working conditions.
RMT general secretary Mick Lynch said: “A financial crisis at [London Underground] 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.”
Mr Lynch added that RMT was still open to continuing talks with a view to calling off the strike.
Andy Lord, TfL’s chief operating officer, 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.
“The devastating impact of the pandemic on TfL finances has made a programme of change urgently necessary and we need the RMT to work with us, rather than disrupting London’s recovery.
“We’re urging them to do the right thing for London, talk to us and call off this unnecessary action.”
Tube drivers on the Central and Victoria lines are also striking every Friday and Saturday night over the Night Tube, a separate dispute that is set to continue until June.
It comes as TfL’s short-term funding deal with central government was given another extension – this time for just two weeks.
The transport agency has had its finances decimated by the pandemic and has a hole in its budget of more than £1m.
A spokesperson for the agency said: “There is no UK recovery from the pandemic without a London recovery and there is no London recovery without a properly funded transport network in the capital.
“It is essential London receives the sustained long-term government funding that is vital for the coming years if a period of ‘managed decline’ of London’s transport network is to be avoided.
“We have agreed with the government that our existing funding agreement will be extended until 18 February so that these discussions can be concluded.”