LAGOS/LONDON - Nigeria's newly operating Dangote refinery is due to deliver its first fuel into the local market within weeks, four sources told Reuters, in a key milestone toward long sought energy independence for Africa's top oil exporter.

Nigeria has relied on imports for most of the fuel it consumes but the $20 billion refinery is set to turn it into a net exporter of fuel to other West African countries, in a huge potential shift of power and profit dynamics in the industry.

The first fuel should be hitting the market "anytime from now", a senior Dangote executive, speaking anonymously as the details were not public, told Reuters.

The development means Nigeria has been exporting less oil in recent months and could soon import less gasoline and diesel for domestic needs from oil majors and trading houses – a multi-billion dollar annual trade that has persisted for decades.

Nigeria's national oil firm NNPC Ltd is set to supply the 650,000 barrel per day (bpd) plant with 4 million barrels in March, a source with direct knowledge of the matter told Reuters, bringing the total supplies since December to 12 million barrels, or roughly 100,000 bpd.

The source added that NNPC was allocating cargoes to the refinery on a spot basis. "They nominate and (NNPC gives) them based on availability; no minimum or maximum."

Dangote is also set to receive two cargoes of U.S. WTI crude from oil trader Trafigura, two of the sources said.

Neither privately-owned Dangote refinery nor state-owned NNPC immediately responded to an official Reuters request for comment.

The refinery, Africa's largest, was built on a peninsula on the outskirts of the commercial capital Lagos by the continent's richest man Aliko Dangote.

It is producing and storing diesel, naphtha, jet fuel, and residual oil, one of the sources said. Tests to determine if the supplies meet quality standards are in final stages, the Dangote executive added.

Reaching full capacity could take months and Dangote has said it will start by refining 350,000 bpd and aims to ramp up to full production later this year.

(Writing by Noah Browning; Editing by Elaine Hardcastle)