Bola Tinubu, has explained what he felt President Muhammadu Buhari meant by the directive given to security operatives to deal ruthlessly with political thugs who attempt to snatch ballot box during the elections.
"The commission came to the conclusion that proceeding with the election as scheduled is no longer feasible".
Just five hours before polling stations were due to open in Nigeria, the country's presidential election was cancelled and rescheduled for next weekend.
One ruling party campaign director in Delta state, Goodnews Agbi, told The Associated Press it was better to give the commission time to conduct a credible vote instead of rushing into a sham vote "that the whole world will criticise later".
Uche Secondus, chairman of the PDP, also criticized the move, calling it "dangerous to our democracy and unacceptable".
Mr Buhari says he has built a strong foundation for prosperity, but his rival says Nigeria is not functioning.
Yakubu said INEC struggled to prepare elections involving around 90 political parties, 23,300 candidates and 84 million registered voters, while some commission offices in the east were burned in what he called acts of "sabotage".
In a separate statement, Buharai urged Nigerians to "refrain from all civil disorder and remain peaceful, patriotic and united".
If the electoral commission knew about complications, why wait until the final moment to announce a delay, asked Godspower Egbenekama, spokesman for the Gbaramatu kingdom in Delta state in the restive south.
His words were echoed by Abubakar, who called for "patience".
"Any of them who loses Should respect the Creator of Nigeria and the World and should disrespect himself and his views and those influencing him".
Voters across Nigeria - Africa's largest economy, top oil producer and most populous nation - also said they were unhappy.
"As chairman of INEC and on behalf of the commission, we take full responsibility for what happened and we regret any inconvenience our decision might have caused", he added. "I do not really understand why they suspended the election", he said. Officials said they had been unable to distribute ballot papers and counting machines on time.
The commission also confirmed that campaigns would remain closed, for the presidential election.
He stressed that postponing the elections was a hard decision, but was necessary for successful delivery of the elections and to consolidate on Nigeria's democracy. Authorities had bolstered security in much of the country.