The strike action – over the rosters used to staff the Night Tube – are due to continue on the two lines for each weekend until December 18, when a 24-hour walkout is planned on five lines.
Almost 30,000 passengers used the Night Tube when it resumed for the first time in 20 months last weekend. Transport for London said passenger numbers overnight last Saturday were about a third of pre-pandemic levels.
This was despite the RMT union calling drivers out on strike, which is thought to have deterred some travellers.
However, TfL said it was able to run a “near full service” of five or six trains an hour on the Victoria line, though there were fewer trains on the Central line, which is believed to be more heavily unionised.
TfL said there were 15,115 Night Tube journeys between 00:30am and 04:30am last Sunday on the Central line - 32.1 per cent of pre-pandemic Night Tube levels.
There were 14,555 journeys on the Victoria line - 39.2 per cent of pre-pandemic Night Tube levels.
About two-thirds of journeys were made before 2am.
Six more nights of action are planned by the RMT prior to the 24-hour walkout on the last Saturday before Christmas that will also involve the Jubilee, Northern and Piccadilly lines.
TfL said there was the potential for “little or no service” on the Victoria and Central lines for the next three weekends.
This is because a different group of drivers is booked for Night Tube shifts each weekend – and attendance may vary week to week.
Nick Dent, London Underground’s director of customer operations, said: “We’re urging Night Tube customers to check before they travel this weekend ahead of more disruptive RMT strike action on the Central and Victoria lines.
“While I’m pleased we managed to run a safe and regular service on the Night Tube last weekend despite strike action, there is still a chance of severe disruption this weekend and up to Christmas.
“We’ve been in talks with the RMT for months to try and avoid this needless strike action. I apologise to customers for the disruption they may face and urge the RMT to continue talks with us, rather than threatening London with further strikes at a crucial time for its recovery.”
TfL announced recently that night services on London Overground will be restored on Friday and Saturday nights between Highbury & Islington and New Cross Gate from December 17. No strike action is planned to disrupt Night Overground’s return.