London Underground drivers are set to go on strike for the third time in as many weeks after talks to resolve a Night Tube dispute were unsuccessful.
Rail, Maritime and Transport union (RMT) members will take industrial action on the Central and Victoria lines from 20:30 GMT on Friday.
The RMT said Transport for London (TfL) had made a “series of errors” to impose Night Tube rosters without agreement.
TfL has branded the strikes, which also take place on Saturday, “unnecessary”.
On 26 November, a 24-hour walkout caused disruption to six lines throughout the day.
A second round of industrial action took place last weekend with further walkouts expected in the run up to Christmas.
There will be walkouts on the Central and Victoria lines for eight hours from 20:30 GMT on the following dates:
- Friday 10 December
- Saturday 11 December
- Friday 17 December
- Saturday 18 December: also affects Jubilee, Northern, Piccadilly lines from 04:30