BT's decision not to proceed with rolling out the Phorm Webwise service to its 4.7 million broadband customers could deal a heavy blow to the AIM-listed group which has former Chancellor Norman Lamont as its chairman.

But a spokeswoman for Phorm said they continued to work closely with Internet service providers around the world and said there had never been any fixed timeline for a BT launch.

Phorm is also being trialled by South Korean ISP KT while Britain's Virgin Media and Carphone Warehouse are exploring the possibilities of working with the group.