The Public Investment Corporation (PIC), the MTN Group's biggest shareholder, is pushing for changes at the mobile-phone company to avoid the regulatory, legal and political disputes that have cut its share price by more than half over the past four years, BusinessLIVE says.

The PIC built a 26% stake in Johannesburg-based MTN by late November and used that to call for the replacement of chairperson Phuthuma Nhleko, people familiar with the matter said, according to Bloomberg.

The PIC also sent a letter to MTN demanding a board reorganisation, which resulted in the appointment of more politically connected directors. In May, the carrier obliged, announcing Nhleko's planned departure and replacement, along with other director changes and a new separate group of prominent advisers.

MTN CEO Rob Shuter said in an interview in London last week: 'An important thing for them was on our board evolution.'

The PIC was moved to act following a series of disputes in Nigeria, Iran and elsewhere, the sources said.

The biggest of those was a $5.2bn fine in Nigeria in October 2015, which was eventually settled for less than $1bn after about eight months of negotiations.

The PIC wants the new chair, former Deputy Finance Minister Mcebisi Jonas, and the board to resolve outstanding issues such as a $2bn tax dispute in Nigeria, the sources said.

Full BusinessLIVE report