Peter Obi is the top Twitter trend in Nigeria after he pulled out of the presidential primaries race, citing what he called "recent developments" within the Peoples Democratic Party (PDP) which made it "impossible to continue participating and making such constructive contributions".
He said he remained committed to helping Nigeria solve its "deep-seated" issues.
Mr Obi previously served as the governor of Anambra state in the south-east of the country between 2008 to 2016.
One of his main campaign promises was to improve Nigeria's economy and to make the country "productive" . He has previously linked criminality in the country to poverty.
Mr Obi is a businessman and joined the PDP in 2017.
He previously ran as the vice-presidential candidate for opposition politician Atiku Abubakar in 2019 elections.