Londoners will be able to use the 4G mobile network anywhere on the Tube by the mid-2020s under plans unveiled by Transport for London.
The first passengers to benefit from the roll out on the underground will be those using the Jubilee Line, with the eastern part of the line spanning from Westminster to Canning Town to be online by March 2020.
The trial section will exclude London Bridge and Waterloo, which are both waiting additional approval and could be added toward the end of 2020.
At all other stations the access to 4G will span across platforms, tunnels, ticket halls and corridors.
On Friday, TfL said it would deliver connectivity across the entire underground network by the mid-2020s.
“This is a really important step for the millions of people who use the Tube each year,” said Mayor of London Sadiq Khan.
“Introducing 4G and, in the future, 5G will help Londoners and visitors keep in touch and get the latest travel information while on the go.
“London is the best place to live, visit and work – and projects like this will help make it even better.”
There are already 260 wifi-enabled stations on the London Underground and on TfL rail services.
Shashi Verma, chief technology officer at TfL, said: “The London Underground network is an incredibly challenging environment in which to deliver technological improvements, but we are now well on the path to delivering mobile connectivity within our stations and tunnels.
“We have begun the complex work to allow our customers to be able to get phone reception within our tunnels from March 2020, with more stations and lines coming online during the coming years.”
The project will require 2,000 kilometres of cabling to be installed along tunnels and in stations and will require engineers to work week-night shifts to minimise disruption to passengers