Nigerian President Muhammadu Buhari signed the landmark agreement at the African Union (AU) summit in Niger.
The AU estimates that implementing the African Continental Free Trade Area - called AfCFTA - will lead to a 60% boost in intra-African trade by 2022.
It also says that AfCFTA will create the world's largest free trade area.
Recall that President Muhammadu Buhari had refused to sign the agreement saying more consultations were necessary before Nigeria can append its signature to it.
Pres. @MBuhari signs, on behalf of Nigeria, the Agreement Establishing the African Continental Free Trade Area (#AfCFTA), at the opening of the 12th Extraordinary Session of the Assembly of African Union Heads of State and Govt, in Niamey, Niger Republic, July 7, 2019 #AUSummit pic.twitter.com/Y9miko2GBP— Presidency Nigeria (@NGRPresident) July 7, 2019