South African mobile company MTN has fuelled the ongoing insurgency by terror group Boko Haram by failing to disconnect unregistered SIM cards, the Nigerian president has claimed. Muhammadu Buhari made the accusation as South African leader Jacob Zuma made an official visit to Nigeria.

In recent months, mobile networks in Nigeria deactivated 10.7m unregistered SIM cards, which are often used by criminals and terrorists to communicate. Unregistered cards are also used by terrorist groups like Boko Haram, which has killed at least 20,000 people in Nigeria and neighbouring countries since 2009.

"The concern of the federal government was basically on the security, not the fine imposed on the MTN," Buhari said at a joint press conference, according to AFP. "You know how the unregistered GSM are being used by terrorists... That was why (the) NCC asked the MTN, Glo and the rest of them to register GSM.

"Unfortunately MTN was very slow and contributed to the casualties. And that was why the NCC looked at its regulations and imposed that fine on them."

President Zuma did not comment on Buhari's claims.

The Nigeria Communications Commission (NCC) fined MTN $5.2bn (£3.3bn) - an amount that was later reduced by a third to $3.4bn - in October 2015. The record fine was imposed after MTN allegedly failed to disconnect non-registered SIM cards within the allowed deadline.

MTN has already paid $250m and is currently negotiating an agreement. Since the fine was imposed, MTN CEO Sifiso Dabengwa has resigned, while the company shares has plunged. The CEO of MTN Nigeria, Michael Ikpoki, and the head of regulatory and corporate affairs, Akinwale Goodluck have also quit their posts.

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