Foreign election observers have appealed for calm following the last-minute postponement of the Nigerian election by a week.
“We call on all Nigerians to remain calm and support the electoral process”, said a statement from EU, UN and African Union representatives.
President Muhammadu Buhari and his main rival Atiku Abubakar condemned the election delay.
The presidential and parliamentary polls will now be held on 23 February.
Election officials cited “logistical” reasons for the 11th-hour postponement.
In a press conference on Saturday, the chairman of the Independent National Electoral Commission (Inec), Mahmood Yakubu, said the decision to delay had “nothing to do with political influence”.
The two main groups, the ruling All Progressives Congress (APC) and the People’s Democratic Party (PDP), both condemned the move and accused each other of trying to manipulate the vote.
President Buhari, of the APC party, urged Nigerians to “refrain from civil disorder and remain peaceful, patriotic and united to ensure that no force or conspiracy derail our democratic development”.
His main rival, Atiku Abubakar, called for calm, saying: “I’m appealing to Nigerians to please come out and vote and I’m asking them to be patient about it.”
In a tweet he said the administration was trying to disenfranchise the electorate.
The chairman of the PDP, Uche Secondu, said the delay was “dangerous to our democracy”, accusing Mr Buhari of trying to “cling on to power even when it’s obvious to him that Nigerians want him out”.