Africa's biggest oil refinery has been opened in Nigeria, where it is hoped it will alleviate chronic fuel shortages.

Nigeria is a major oil producer but most of this is sent abroad while it has to import the refined fuel used in vehicles and elsewhere.

As a result the country often faces chronic fuel shortages.

This is the problem that the $19bn (£15.2bn) refinery, owned by Africa's richest man, Aliko Dangote, is intended to tackle.

"This is a game-changer for the Nigerian people," said President Muhammadu Buhari.

The plant, which is not yet operational, has the capacity to produce about 650,000 barrels of petroleum products a day - more than enough to supply the country's needs. It also includes a power station, deep seaport and fertiliser plant.

Nigeria's existing refineries have been completely shut down for over three years owing to oil theft, pipeline vandalism and structural neglect.

If it works as planned, the plant could make a real change to the lives of Nigerians: "Every time there is fuel scarcity, I don't open my shop because there's no light [electricity] to work and I can't buy fuel for my generator," a young hairdresser from Lagos told the BBC.

At Monday's launch, Mr Dangote outlined his hopes for the refinery: "Our first goal is to ramp up production of the various products to ensure that within this year, we are able to fully satisfy the nation's demand for quality products."

However, it is not clear what impact the plant will have on the price of fuel in a country where retail prices are subsidised. The government says these subsidies will soon be removed - last year they took up at least a quarter of the national budget.

Mr Dangote's plant in Lagos, which took nearly seven years to build, is said to be the world's largest single-train refinery, meaning the plant has one integrated distillery system which can produce a variety of products and petrochemicals, instead of having different units for each type of product.

It is one of the last major projects to be inaugurated by President Buhari, who steps down next week after serving two terms in office.

President Buhari will hand power to Bola Tinubu, who won disputed presidential elections in February.

Oil and gas expert Henry Adigun told the BBC that Monday's launch was "more political than technical".