British Telecommunications Plc is taking on Telecom Eireann on its home turf: it has opened an office in Dublin for the business community to provide companies operating in Ireland with access to a data network connecting over 850 locations in North America, Europe and the Pacific Rim, and claims that they can cut their bills by up to 40%; it leases Telecom Eireann lines as far as the Northern Ireland border, then routes the calls on through its Belfast exchange.