TORONTO, Canada, June 28 -- BellSouth Corp. has signed a long-term global supply agreement with Nortel Networks Corp. under which Nortel will supply communications equipment, software and services. In a joint statement, the two companies called the deal a multibillion dollar purchase agreement. BellSouth said the deal will enable it to continue investing in new technologies, including wireless, data, and Internet provider services in US and overseas markets. It also follows the company's strategy of consolidating its purchasing operations to generate volume-based savings and reduce its total number of vendors.