O2 is to join Vodafone and EE in offering free Wi-Fi on the London Tube network. It has signed a deal with Virgin Media that will allow its customers access to the underground Wi-Fi service at no cost from June.

With Virgin Media adding a further 12 stations to the connected wireless network this week, including Bank, Baker Street and Earls Court, the total number of Wi-Fi-enabled stations will come to 120. The service provider has met Transport for London's targets, set out at the beginning of the project.

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From June, O2 customers will be able to log on to the Wi-Fi service anytime they are in range at any of the connected stations. They will not be charged, and details of how to sign up initially will be sent to them by the provider.

With O2, EE (T-Mobile and Orange) and Vodafone all partnering with Virgin Media for free Wi-Fi, it only leaves Three as the only major network yet to do so. Three customers will still have to pay fees if they require use of the network.