MCI Communications Corp could make an alliance or even enter into a full merger with one or more regional Bell telephone companies once they are allowed into the long-distance market, the company, where British Telecommunications Plc holds 20%, told Reuter. It said that discussions had already taken place with some regional Bells about a broad range of future possibilities but No one is making any commitments until after legislation. The company reckons that the legislation allowing Bells to provide long distance service and forcing their local calling markets open to competition would virtually enforce consolidation among the Bells, and possibly between them and long distance carriers. The most attractive partners to MCI are Nynex Corp, Pacific Telesis Group Inc and Bell Atlantic Corp. Pacific Telesis said it would be open to talks on an alliance with MCI but declined to say whether talks had taken place.