MTN has reportedly offered to pay $1.5 billion (R23.1 billion) to settle a record $3.9 billion (R60 billion) fine in Nigeria.

Bloomberg reports the South African-based telecoms giant made a written offer – consisting of cash instalments, bond purchases and network access − on 24 February. The specifics of the offer were detailed in a letter to the Nigerian government from one of MTN's lawyers, and former US attorney general Eric Holder.

According to the letter, MTN's proposal includes the $250 million (R3.8 billion) "good faith" payment made last month in order to continue negotiations, as well as a further R7.7 billion in five annual instalments between the signing of an agreement and the end of 2020.

The company also reportedly pledged to purchase R6.2 billion of Nigerian sovereign debt issued on international markets in 2016-2017 "as a demonstration of its commitment to and confidence in the Nigerian economy". In addition, MTN would give the government access to its fibre network until 2020, an offer the company valued at R5.4 billion.

The Senate Committee on Communications met to discuss the matter on Thursday and concluded the negotiations with MTN must continue for two more weeks, after which the parties need to report back to the Senate on the outcome of discussions.

MTN spokesperson Chris Maroleng could not confirm or deny the offer, but if any resolution was reached, shareholders would be informed through the Johannesburg Stock Exchange news service (SENS).

MTN this morning renewed an earlier cautionary announcement on SENS, asking shareholders to continue to exercise caution when dealing with its stock.

"MTN is aware of the various reports which appeared in the press yesterday regarding the fine. MTN has previously advised shareholders not to make decisions based on press reports and MTN again urges its shareholders to refrain from doing so."

The company reiterated it continues to engage with the Nigerian authorities "in an attempt to ensure an amicable resolution to this matter in the interests of MTN Nigeria, its stakeholders and the Nigerian authorities".

MTN's full-year results, announced last week, were hit hard by the telco's Nigerian woes − with basic headline earnings per share falling over 51% for the year. During the results announcement, MTN said it had made a R9.3 billion provision for the fine.

Africa's largest mobile operator was slapped with a $5.2 billion (R80 billion) penalty by the Nigerian Communications Commission last October for failing to disconnect 5.1 million unregistered SIM cards on its Nigerian network. In early December, the fine was reduced by 25% to $3.9 billion.

Earlier this week, Nigerian president Muhammadu Buhari publicly rebuked MTN for moving too slowly when disconnecting unregistered SIM cards, which he said were being used by terrorists, including Boko Haram.

"Unfortunately, MTN was very slow and contributed to the casualties," Buhari said when speaking at a joint press conference alongside South African president Jacob Zuma.

MTN shares have declined over 22% since the fine was announced in October, with the share closing at R147.50 on Thursday. The Johannesburg-based company currently has a market cap of around R272 billion.

Nigeria's subscriber registration requirements saw the group disconnect 6.7 million subscribers in the country last year. MTN currently has 61.3 million active customers in Nigeria, while it has 232.5 million subscribers across 22 countries in Africa and the Middle East.