MTN Group Ltd., Africa’s largest wireless operator, has appointed the head of its Rwanda unit, Ebenezer Asante, to run the company’s Ghanaian operations, a source has revealed.

Asante will move to the West African country after the unit’s previous chief executive officer, Serame Taukobong, resigned.

MTN will hire an internal candidate to replace Asante in Rwanda, the source said. Ghana is MTN’s fourth-biggest market in terms of subscriber numbers, after Nigeria, South Africa and Iran.

MTN spokesman Chris Maroleng declined to comment on the appointment. MTN Ghana spokeswoman Georgina Asare Fiagbenu also declined to comment.

Johannesburg-based MTN, which has about 228 million subscribers across 22 countries as of March 31, is shuffling management for the second time in less than a year as it seeks to generate more revenue from its smaller markets.

The company is battling regulatory pressure and tough competition in Nigeria and South Africa. Its shares traded 1.1 percent higher at 233.39 rand as of 11:41 a.m. in Johannesburg, valuing the company at 431 billion rand ($36 billion).

Asante previously worked for MTN Ghana as a sales and distribution executive and helped to, more than double, its customer base to 9.9 million in five years, according to the company’s website.

The unit now has about 14.2 million subscribers, compared with 3.9 million in Rwanda