Nigeria’s government approved major transport and energy investments, including a stake in a giant private refinery, that are expected to cost $15.4-billion.

Ministers in the West African nation signed off Wednesday on the state-owned Nigerian National Petroleum Corp.’s proposed purchase of a 20% stake in a refinery being built by Aliko Dangote, Africa’s richest person, for $2.76-billion. They also agreed to the rehabilitation of two other NNPC-controlled refineries and the construction of a 1,400-kilometer (870-mile) railway.

The decisions were taken at a meeting of the Federal Executive Council and disclosed at a briefing. Further details weren’t provided.

The investments could help boost output in the nation, which has underinvested in infrastructure and where economic growth has lagged behind the pace of population expansion every year since Muhammadu Buhari came to power in 2015, leading to a decline in average income per capita.

The NNPC said in June that the African Export-Import Bank is raising a $1-billion loan to help the firm buy shares in Dangote’s 650,000 barrel-a-day complex near Lagos, Nigeria’s commercial hub. It’s unclear how the company intends to fund the rest of the acquisition, although one option could be through the supply of crude.

The FEC also authorized the NNPC’s plans to spend $1.48-billion on repairing and upgrading its refineries in the cities of Warri in southern Nigeria and Kaduna in the north, Minister of State for Petroleum Resources Timipre Sylva said. The facilities, which aren’t operational, will be fully rehabilitated in 33 months, he said.

The NNPC has already started work on a $1.5-billion revamp of two refineries in the southeastern city of Port Harcourt.

The FEC gave its approval to a standard-gauge railway that will run from Lagos in the southwest of Nigeria to the city of Calabar in the southeast, said Information Minister Lai Mohammed. The contract, which is worth $11.2-billion, was awarded to state-owned China Civil Engineering Construction Corp. in 2014.

Transport Minister Rotimi Amaechi said in June that the government is in talks with Standard Chartered Plc about arranging financing for the so-called “Coastal Line.” Nigeria had initially expected Chinese lenders to back the project.

Buhari told Nigeria’s National Assembly in 2017 that the State-owned Export-Import Bank of China was soon going to approve a $3.5-billion loan to help start construction.