Hundreds of hotzones will be rolled out across the cities, giving access to the internet for anyone using a wi-fi enabled computer or mobile phone. More cities are expected to be announced during 2006.
The first phase will see hotzones set up in Edinburgh, Leeds, Manchester, Birmingham, Nottingham, Oxford, Cambridge and three London boroughs - Islington, Kensington and Camden.
It is expected that the new wireless internet network will reach more than 4 million people.
Each hotzone will turn broadband-speed internet into radio signals to allow people to surf the net, send e-mails, play online games and make cheap phone calls over wi-fi.
"Providing ubiquitous wireless broadband access, over a network that is available to millions of wi-fi devices, and will be available to the new generation of wi-fi phones, gaming devices and other applications will have a major impact on the way people communicate, work and play in city centres," said George Polk, chief executive of The Cloud.
The hotzones will rival existing mobile phone networks.
Around 25 mobile phone handsets currently have wi-fi chips installed. Pressing a button on the phone allows users to bypass their own mobile phone network to connect to the internet and make cheap broadband phone calls.
Initially the networks will be available to people using BT Openzone, O2, SkypeZones and Nintendo WiFi but The Cloud hopes other service providers will want to join the party.