Nigeria has signed a $23 billion agreement with China to construct three gasoline refineries and a fuel complex in the oil-rich, but gas-starved African nation.

The deal between state-run Nigerian National Petroleum Corporation and China State Construction Engineering Corporation Limited is expected to add 750,000 barrels a day to Nigeria's refining capability.

Nigeria said in a statement it wants to reduce the approximately $10 billion a year it spends to import refined fuel.  

It was not immediately clear when construction would begin or where the refineries would be placed.

Production at Nigeria's four existing refineries has fallen drastically due to corruption and mismanagement.

Militants in Nigeria's Niger Delta have carried out attacks on the oil industry since 2006, saying they want the region's residents to get more of its oil wealth.

More than four years of attacks on the pipelines in the delta have sharply cut Nigeria's oil output, allowing Angola to rival the country as Africa's leading oil producer.

Some information for this report was provided by AP and AFP.