The Democratic Republic of Congo has signed a $14 billion (£10 billion) deal for what is billed as the world's largest hydro-electric project with a consortium of Chinese and Spanish companies.
The Inga 3 Dam will generate 11,000 megawatts of electricity when complete but progress has stalled for decades.
This is not the final green light to build the mega project to harness hydroelectric power from the Congo River in the country's west. However, the government called it an important step forward.
DR Congo signed what it calls an exclusive development agreement meaning the Chinese and Spanish firms can now start raising the money for the project before putting in a formal bid.
Only 10 per cent of the population of DR Congo has access to electricity. The project is expected to improve supply to residences and businesses, including the mining industry.
The World Bank pulled out of Inga 3 plans in 2013, scaring off early investors.
Civil society groups have opposed the project because of President Joseph Kabila's direct control over the negotiations and environmental concerns.
The business model of Inga 3 depends on exporting power beyond the DR Congo's borders, South Africa signed up to buy 2,500 megawatts from Inga 3 in 2013, reports BBC.
Transmission lines will cost another $4 billion, on top of the facility's $14 billion price tag.