Virgin Media has announced plans to create a free Wi-Fi network to cover London, to compete with the often unreliable 3G mobile phone network and a patchwork of other Wi-Fi services.

In a speech to investors, Virgin Media's chief executive, Neil Berkett, said Virgin Media was in "quite advanced negotiations" with London councils over permission to install wireless routers across the city.

The capital, like many other cities, is already served by BT Openzone, one of the largest Wi-Fi networks. However, BT charges for access to non-BT customers.

Virgin's service would provide non-customers with a free but relatively slow 0.5 megabits per second connection – sufficient for email and basic web browsing.