The Independent National Electoral Commission (INEC) says it is impossible for any candidate at this stage to withdraw from the presidential election.
The election is coming up on February 16.
The spokesperson of INEC chairman, Rotimi Oyekanmi, stated this in reaction to the statement earlier on Thursday by the candidate of the Allied Congress Party of Nigeria (ACPN), Oby Ezekwesili, that she was withdrawing from the poll.
Mrs Ezekwesili said she was withdrawing so as to help form a coalition against the ruling All Progressives Congress (APC) and the major opposition Peoples Democratic Party (PDP) at the general elections.
The ACPN leadership, including Mrs Ezekwesili's running mate, Gani Galadima, shortly after at a press conference disowned her and announced they would be joining the campaign for the reelection of President Muhammadu Buhari of the APC.
In line with the commission's timetable for the election, the last day for withdrawal by candidates or replacement of withdrawn candidates by political parties for the presidential and National Assembly elections was November 17, 2018.
"It is impossible for any presidential candidate to withdraw from the race now," Mr Oyekanmi said.
"Therefore, the deadline for Ezekwesili or any candidate in that category to withdraw or be replaced has passed," he said.
The Bring Back Our Girls #BBOG) convener had said she withdrew from the February 16 presidential election to help build a coalition to defeat the APC and the PDP in the election.
She said her decision was taken despite resistance from her party, which has now declared support for Mr Buhari's reelection bid.
But INEC said Mrs Ezekwesili's withdrawal changes nothing as her party and name will still appear on the ballot.
"Her party will appear, her passport will appear and her name will appear. So it doesn't change anything as as far as we are concerned," Mr Oyekanmi