The former finance minister, had also announced that she will also be joining US investment bank, Lazard’s sovereign advice division.
Okonjo-Iweala who tweeted via her Twitter handle, @NOIweala said: “I’m excited to join GAVI to immunize 300 million more children in the next five years and save 5 million to 6 million more lives.”
The new portfolios, however, follow her second stint as Nigeria’s finance minister, which ended in May after the Goodluck Jonathan-led government was voted out of office.
Okonjo-Iweala has spent the past three decades working on fiscal management and governance systems in Africa through 25 years at the World Bank, most recently as a managing director, and twice as finance minister in what is now the continent’s biggest economy.
She has although, recently come under sharp criticisms particularly by Governor Adams Oshiomhole of Edo State, over issues bordering on alleged corruption in the last administration.
Okonjo-Iweala has argued that her work on transparency and anti-corruption as finance minister under both Mr Jonathan and Olusegun Obasanjo has been unfairly “brushed aside.”
By Ikenna Asomba