Phase one includes the first 4,200m runway, taxyways a passenger terminal and a cargo terminal. The Rwandan government has signed the contract with the African division of Portuguese construction firm Mota-Engil.
Phase one is believed to be worth $418 about half of the total planned project.
Phase two will include a second runway and additional terminals.
The current international terminal in Kigali has a capacity of 1.6million while the new first terminal will cater for 1.7 million.
Phase two will raise the capacity to 4.5million.
In an interview with Arabian Aerospace last year the Rwandan CAA said that the existing airport could become a business aviation airport but would not make any plans until after the turnkey contract was awarded.
The new airport is planned to open in 2018. Work will begin in June next year.
Rwanda said in a statement that Mota-Engil would operate the airport for 25 years, with an option to extend another 15 years.
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