Comcast Corp. may receive an estimated $ 109 million in backing for its United Kingdom cable TV and telecommunications ventures as a result of agreements it has struck with Warburg, Pincus & Co. and Bankers Trust Intl.Striking a deal The cable company said it has struck a deal with the venture capital firm and merchant banker in which the two concerns may invest that sum in its British cable and telephony business, subject to regulatory approvals. Apax Partners & Co. Corporate Finance Ltd., a London international investment banker, acted as Comcast’s financial advisor. 3 in U.K. At present, Philadelphia-based Comcast has three cable TV franchises in the U.K., encompassing 1 million homes, in Cambridge, Birmingham and North London. After receiving its license in 1989, the U.S. cabler has been in the process of wiring the areas. Warburg, Pincus associate Ken Rotman said the investment reflects the company’s long-held goal of making a strategic investment in Britian’s infant cable industry. “The country is almost completely unwired and we believe there is great demand for multichannel TV,” said Rotman. Series of investments This is the latest in a long string of investments by U.S. cablers in the British cable business, which started in the late 1980s after U.K. regulators eased limits on foreign control of cable operations. U.S. companies own or control stakes in nearly three-quarters of Britian’s 135 cable franchises. Cable penetration remains very low in Britian, but some have questioned its viability when DBS services such as Rupert Murdoch’s Sky Television reach so many homes. But one reason it is particularly attractive is that cable operators , in contrast to the U.S., are allowed to offer basic phone service. That means they can compete directly against British Telecom.