British mobile service providers Three and EE have become the first of the four mobile networks in the UK to reach an agreement regarding 4G and 5G coverage across the whole London Underground.

The two companies will provide high-speed connections to their customers across the London tube, enabling them to make phone calls or stream video while on the go.

The move is expected to generate millions of pounds in much needed revenue for TfL (Transport for London), which has been in financial deep waters in the past few years. It is also part of TfL's wider plans to increase income sources in addition to fares and break even by 2023.

4G had already been piloted for the eastern end of the Jubilee line since March last year. However, plans for the entire tube network and Crossrail were laid out on Tuesday.

According to the plans, TfL hopes to connect parts of central London by the end of next year (2022). Works are already underway at stations including Oxford Circus, Tottenham Court Road, Bank, Euston and Camden Town.

Crossrail should be fully 4G by the same date, while the entire project is due to be completed across the Underground by 2024.

TfL awarded a 20-year contract to BAI Communications this summer to install the infrastructure required for 4G - and any subsequent upgrade to 5G.

A very welcome move

London Mayor Sadiq Khan welcomed the move saying it "will make a huge difference to passengers".

"Investing in London's connectivity and digital infrastructure is one important way we are helping to stimulate our city's economy. It also represents a significant step towards ensuring the whole tube network has 5G-ready mobile coverage", he added.

Philip Jansen, chief executive of BT Group; which owns EE, said the roll-out would enable London to "leapfrog" rival cities in terms of its digital connectivity.

Shashi Verma, chief technology officer at TfL, said the deal would "provide a long-term revenue stream for TfL and support economic growth across the city".

A Vodafone spokesman said the company expects to sign up with BAI next month.