Citicorp joined a growing list of banks by signing up with AT&T Corp.'s professional services unit to manage its global data communications network.
Bank officials estimated in Tuesday's announcement that the $750 million, five-year contract - the biggest single-vendor networking contract in the financial industry - will save Citicorp $250 million by consolidating 11 telecommunication links onto a Global Data Network run by AT&T Solutions.
"This partnership with AT&T will improve our overall network service quality and reliability, and at the same time lower our operating costs," said Stan Welland, head of Citibank's global technology infrastructure division.
"After long and careful thought, we decided to focus on our core competency, which is banking," said Mr. Welland, adding that AT&T's worldwide capabilities would allow the bank to use Internet-based standards for communicating with its offices in 98 countries.
Other financial clients of AT&T Solutions include J.P. Morgan, Wells Fargo, Chase Manhattan, and MasterCard International.
The agreement will allow Citicorp to ship more computer data among employees and to its customers, which could prove important in an age of electronic commerce.