Nigeria's biggest mobile phone operator MTN has warned that its network faces shutdown due to fuel shortages that have crippled the nation.
The company, the biggest subsidiary of the South Africa-based MTN Group, said it needed a "significant quantity of diesel in the very near future to prevent a shutdown of services across Nigeria".
"If diesel supplies are not received within the next 24 hours the network will be seriously degraded and customers will feel the impact," it added on its Twitter account @MTNNG on Saturday evening.
Nigeria has been increasingly hit by fuel shortages in recent weeks because of a long-running row over controversial subsidy payments.
Despite being Africa's biggest oil producer, Nigeria lacks domestic refineries, forcing crude to be exported and products such as petrol and diesel to be imported.
To keep costs to consumers low, the government sets prices below the market rate and pays the difference to importers.
But the global slump in oil prices has hit Nigeria hard and oil marketers claim they have not been paid in full.
Fuel depots have closed as a result pending payment of the arrears, with the situation worsened after oil and gas union workers walked out over the sale of two oil blocks.
The crisis comes just days before President Goodluck Jonathan leaves office, handing over power to Muhammadu Buhari this Friday.