Nigeria's Dangote refinery will hit production of 550,000 barrels per day (bpd) this year, equivalent to 85% of capacity, but it is having to increase crude imports due to insufficient domestic supplies, the plant's CEO said on Saturday.

Chief Executive Aliko Dangote said the 650,000-bpd capacity refinery, which is the largest in Africa, had only received five crude cargoes from state oil firm NNPC since it started operating earlier this year, instead of the 15 it expected.

"That is why we went ahead and bought some Brazilian crude, we also got U.S. crude. Anytime we go to IOCs (international oil companies) they say go to brokers," Dangote said during a tour of the facility on the outskirts of Lagos.

He added that brokers were charging a $4 mark-up per barrel of crude. NNPC had in the past agreed to supply the refinery 300,000 bpd but it is struggling with low production and some of its crude is being exchanged for gasoline imports. The Dangote refinery, built at a cost of $20 billion, began production in January after several years of delays.

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