The deal, announced yesterday, will enable Telkom cellphone users to roam on MTN's network outside the large urban centres where Telkom has no infrastructure.
Telkom yesterday confirmed its intention to enter the mobile voice and data business.
It said it had placed orders for the building of 2000 base stations in high-density areas during the next two years.
In terms of the agreement, Telkom and its customers will have national access to MTN's 2G and 3G network.
Telkom said its capital programme for mobile-related investments over the next five years was expected to be about R6-billion.
"The roaming agreement enhances Telkom's ability to offer customers extensive, national mobile coverage from day one of the launch.
"It is crucial to the delivery of a successful mobile strategy," Telkom said.
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