Nigerian president Muhammadu Buhari will be the deciding factor in MTN's pending $5.2 billion (R74 billion) fine in Nigeria.

"The [Nigerian communications] minister [Adebayo Shittu] said in Lagos that it will be up to the president to determine which direction to go since MTN asked for leniency," ministry spokesman Tajudeen Kareem told Reuters.

Last month, the Nigerian Communications Commission (NCC) slapped MTN with the hefty fine for failing to disconnect over five million unregistered SIM cards on its network. The fine is the equivalent of around one trillion naira and is the combination of a fine of N200 000 for each unregistered subscriber.

Nigeria has been pushing operators to verify the identity of their subscribers because of concerns over unregistered SIM cards being used for criminal activity, as well as worries over links to Islamist militant group Boko Haram.

MTN is the largest mobile phone operator in Nigeria, and the West African nation is also MTN's biggest market. The telco had 62.5 million subscribers in Nigeria as of the third quarter this year and the country accounts for about a third of the MTN group's revenue.

The operator has not provided an update on the status of the fine since 16 November, when it announced the deadline for the fine payment, set for that day, had been extended. At that time, it said MTN's executive chairman, Phuthuma Nhleko, was in Nigeria and had personally met with the Nigerian authorities to continue the ongoing discussions regarding the fine.

MTN's stock price has fallen around 25% since the fine was announced on 26 October and over 35% year-to-date. At around 10am this morning, the group's shares on the JSE were worth R143.20 each.