Warid Telecom recently lowered the rate even further, to Ush1 per second from 6 a.m. to 6 p.m. For short message service (SMS) services, Airtel is offering unlimited text messages to its subscribers for Ush200 per day within its network.

While the reduced telecom prices, last year and over the past few years, have resulted in a reduction in general price inflation because of the importance of communication services, operators have suffered a revenue decline as users who owned a single mobile phone were forced to hold two and spread their expenditure on telecom services among the operators. Phone users today spread their expenditure on phone calls to avoid the high tariffs that are charged on calls across networks they are not subscribed to.

"When inflation declined significantly in October 2010, it was because of airtime," a report by the Uganda Bureau of Statistics said. "When you make a shift or a jump, you reduce inflation because the income that would have been spent on airtime is saved."

A price war similar to the one in Uganda has been raging in the Kenyan market, where Airtel has been out to erode Safaricom's dominance in voice. Kenyan regulators are yet to propose anything resembling minimum tariffs. But with the telecom market in Uganda headed for price controls, the rest of the region will be looking to see whether the regulator's hand improves the players' margins.