Last year, the government said the Port Harcourt refinery will start processing crude at the end of 2022. However, successive oil ministers and NNPC Ltd executives have announced a series of unsuccessful plans to restart, revamp or expand the refineries, Reuters reported.

Heineken Lokpobiri, who this week resumed as Nigeria's minister of state for petroleum, inspected ongoing refurbishment at the two-unit 210,000 Port Harcourt refinery.

"From what we have seen here today, Port Harcourt refinery will come on board by the end of the year," he said, adding that two other facilities in Warri and Kaduna will start processing crude between the first quarter and end of 2024.

Lokpobiri said "our objective... is to ensure that in the next few years, Nigeria stops fuel importation."

Nigeria, Africa's top oil producer, imports almost all its refined fuel needs to inadequate capacity and poor maintenance.

Four state-owned decrepit refineries with a combined 4450,000 barrels per day, 110,000 barrels Kaduna plant in the north and three units in the oil-rich Niger delta including the 125,000 barrels Warri refinery, have been shut down for years.

The Port Harcourt refinery is undergoing a $1.5 billion upgrade after Italy's Tecnimont was awarded the contract to carry out the work in 2021. The revamp will take 44 months to complete, the oil ministry said in April last year.

The country is now pinning its hopes of ending fuel imports on a 650,000 barrels per day refinery being built to by Aliko Dangote, Africa's richest man.