Tele-Communications Inc. and MCI Communications are discussing a potential partnership.TCI, the nation’s largest cable operator, has been in talks with a number of large players in the telecommunications and entertainment industries. However, MCI, the U.S.’s second-largest long distance carrier, has been very quiet about its plans. So far, TCI has been partnered with MCI rival AT&T on pay-per-view experiments in the Denver area and is a long-rumored marriage in the making. A formal partnership between a cable company and telco provider would follow a similar deal between Time Warner Inc. and U S West. The talk’s disclosure came from MCI’s chairman Bert Roberts, who also announced that he was exploring possible business combinations with the cellular units of the seven Baby Bells.