According to investment analyst Nadim Mohamed, who is a partner at First Avenue Investment Management, the year 2013 will probably be a more challenging year for two of South Africa's operators - MTN and Vodacom - even though they have "good leadership and assets."

Noting that the above-average margins and ROEs reported by MTN and Vodacom will apparently be difficult to defend in 2013, Mohamed said that the two operators will likely face much stronger competition from rivals like Bharti and Etisalat.

Mohamed's projections of a difficult 2013 for MTN and Vodacom come against the backdrop that the two operators have had a "strong competitive advantage" in the South African market where they reported "improved earnings before interest, taxes, depreciation, and amortisation (Ebitda) margin", even in spite of lower terminating charges and pricing from 8ta and Cell C.

Pointing out that MTN and Vodacom have shown strong growth and have sustained their dominant position in the Africa market, Mohamed said that the two operators have an inherent scale advantage and network effect because they are among the leading operators in the markets in which they operate.

Meanwhile, citing another reason - other than stronger competition - for his projections of a challenging 2013 for MTN and Vodacom, Mohamed said: "Regulators appear to be increasingly more active as we've seen in Ghana where MTN have been barred from adding new subscribers because of deteriorating network quality."