Transport chiefs have said they are “disappointed” at the planned strikes, warning it will “cause unnecessary disruption”
What dates and times are the strikes planned?
The RMT action will see its members conduct a walk-out on the Victoria and Central lines from 8.30pm on Friday until 8am on Saturday, and from 8.30pm on Saturday until 8am on Sunday.
Set to be the longest strike in London Underground history, it will take place from Friday January 7 and continue each weekend until June.
It was followed with drivers on the Northern, Piccadilly and Jubilee lines also staging a walk out for 24 hours – meaning five Underground lines had fewer or no trains on the final Saturday before Christmas.
Why is the RMT striking?
TfL announced London’s round-the-clock Night Tube service would resume from November 27 on the Victoria and Central lines.
The east-west Central Line and north-south Victoria Lines were set to operate overnight on Fridays and Saturdays each week.
Drivers will be rostered to work up to four night shift weekends per year, Andy Lord, London Underground’s managing director, said on January 7.
But the RMT says the rota changes have resulted in “unacceptable and intolerable demands” on its members and their work-life balance.
Following the first batch of strike action, RMT general secretary Mick Lynch said members had remained “solid and determined”.
“This issue isn’t going away,” he said.
“With action scheduled for the next six months there is only one way forward and that’s for serious and genuine talks aimed at a negotiated settlement.”
It claimed TfL bosses rejected its offer to suspend strike action.
Which lines will be impacted by the latest strike?
RMT members will stage a walkout on two Night Tube lines every weekend evening – the Victoria and Central line.
The RMT has not ruled out strikes on other lines if Underground bosses don’t meet its demands, saying its legal mandate to strike extended to other Tube lines.
This means although they’re not facing strike action, the large-scale protest is expected to have a knock-on effect on other lines on the network.