(ShareCast News) - Carillion's 60:40 joint venture with telecoms group telent, Carillion telent, has signed a three-year extension to its framework agreement with BT's Openreach to provide a wide range of services. These include the maintenance, extension and repair of the telephone and data network in the North East, Midlands & Wales, South West and London & North Home Counties of England.The extension also includes the delivery of asset assurance works, notably poling and related activities, for England and Wales, and the initial three-year period runs until the end of 2021.Carillion said the extension builds on an eight-year partnership between Openreach and Carillion telent, during which the JV has been Openreach's main delivery partner for the management, maintenance and upgrading of its broadband network. The framework is expected to generate up to £900m of revenue over three years - with Carillion's share at over £500m - and up to £1.5bn over five years, as the agreement provides for a two-year extension, subject to performance. Chief executive Richard Howson said: "We are delighted to have agreed this extension to our framework agreement with Openreach that reflects the strong partnership we have built with Openreach over the last eight years as its main delivery partner for the management, maintenance and upgrading of its broadband network. We look forward to continuing this relationship and to supporting Openreach in delivering its objectives for further enhancing the services it provides for its customers."At 0825 GMT, the shares were up 3.4% to 228.20p.