BT Group signalled its return to the mobile market by launching a Blackberry-style smart-phone as part of its broadband deal for users to surf the web and make calls when not at home.

"Communications services are converging, and it is clear that customers want consistent access to the things that matter not only at home, but in the palm of their hands wherever they are," said Consumer managing director John Petter.

BT is among the few large telecom groups in Europe not to own a mobile network after it demerged its mobile operation in 2001.

Consumers will have a choice of two smart phones from Taiwan-based High Tech Computer Corp (HTC) which will connect to the internet at broadband speeds and provide cheaper calls when in a WiFi hotspot.

The Blackberry e-mail device was originally popular with business executives but it is increasingly attracting a wider consumer market. Consumers are also moving to mobile networks and away from landlines to make their calls.