McCaw Cellular Communications Inc, the Kirkland, Washington company 22%-owned by British Telecommunications Plc, yesterday took a big step forward in turning its dream of seamless cellular telephone service across the US with the announcement that subscribers in New York, New Jersey, Florida, Nevada, Pittsburgh, Sacramento, the Pacific Northwest and Canada will be able to use the local system as if it were their own, rather than having first to key in a different access code in each region. In the second phase, all dissimilar equipment in its own network will be linked, and that will be completed by the end of the year. The third phase will involve persuading other independent cellular operators to come onto its North American Cellular Network. It is using the Cellular One name wherever it is in control or where the local company agrees to the switch; in New York, the Metro One service changes its name to Cellular One. McCaw now claims more than 1m of the 6m US subscribers.