LONDON -- Standard&Poor's CreditWire 10/13/97 -- Standard&Poor's today assigned its preliminary triple-'A' rating to Nippon Telegraph&Telephone Corp.'s (NTT) Y1 trillion shelf registration program for the Japanese market. This is a renewal of a Y600 billion shelf registration program that expired Oct. 11, 1997. The rating is based on NTT's dominant position and important role in the Japanese telecommunications market, as well as its strong financial profile compared with major international peers. Despite increased penetration by Japan's new common carriers, NTT maintains a very strong share in the domestic telephone market. Company earnings are improving as a result of successful rate rebalancing and continued growth in the Japanese cellular phone market. However, the competitive picture