The contract covers ticket offices, escalators and platforms, though it is not possible to provide connections in tunnels.

The WiFi network will be free at first when it is unveiled in July, becoming pay as you go after the Games.

A total of 80 stations will enjoy free WiFi by this summer, and another 40 by the end of 2012.

During the Olympic and Paralympics up to three million more passengers than usual could use the tube network each day.

"It's vital that we harness the massive opportunities stemming from the digital revolution by creating a vibrant, world class industry to attract investment and create jobs for Londoners," said London Mayor Boris Johnson.

"This is a fabulous new and free resource which will be in place from this summer when London is being showcased on a global stage and playing host to millions."

Neil Berket, Virgin Media's chief executive, said: "We'll help people make the most of the city and will continue to evolve the service, ensuring everyone can benefit from a service London will be proud of.

"This latest innovation is great news for tube customers, who now have access to emails, web and social media underground for the first time.

"It's also delivered at no cost to fare payers and taxpayers."

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