Nigeria's electoral commission on Saturday postponed presidential and parliamentary elections for one week, just hours before polls were due to open.The two main political parties have condemned the move and accused each other of orchestrating the delay as a way of manipulating the vote.
Independent National Electoral Commission (INEC) chairman Mahmood Yakubu said the timetable was "no longer feasible."
He addressed an emergency session in Abuja after widespread reports of problems with the delivery of election materials, including ballot papers.
He said the delay was necessary to give the commission time to address vital issues and "maintain the quality of our elections", but did not provide further details.
"Consequently, the commission has decided to reschedule to Saturday February 23, 2019," he told reporters.
Parliamentary elections for 360 seats in the lower House of Representatives and 109 seats in the Senate will be held on the same day.
Governorship and state assembly elections will be pushed back to March 9, Yakubu said.
Voting had been due to start at nearly 120,000 polling stations at 0700 GMT, with 73 candidates on the ballot.
Not the first time for election delay
President Muhammadu Buhari, 76, was set to seek a second term of office against a stiff challenge from the main opposition candidate, former vice president Atiku Abubakar, 72.
Buhari's campaign spokesman Festus Keyamo, for the ruling All Progressives Congress, (APC) said the news was a "huge disappointment" and hit out at INEC for being unprepared.
For his part, Abubakar of the main opposition Peoples Democratic Party blamed the Buhari government for "instigating the postponement" but called on his supporters to remain calm.
"We will overcome this. You can postpone an election but you cannot postpone destiny," he added in a statement.
In 2015, Nigeria's elections were postponed for six weeks, due to security concerns linked to the Boko Haram insurgency.
Security continues to be a challenge, with the run-up to the elections marred by violence.
On Friday, officials in north-west Nigeria reported the discovery of the bodies of 66 people, 22 of them children and 12 women, killed by "criminal elements" according to the governor of Kaduna state.
No cause for the violence was given but Kaduna has long been a centre of deadly unrest, fuelled by long-standing ethnic and religious tensions.
