The president directed that "all efforts should be made to provide relief to those injured in the unfortunate incident".
President Muhammadu Buhari is "deeply saddened" by the deaths in a stampede in a church event in Port Harcourt, Rivers State.
The police have confirmed that 31 people were killed on Saturday at the stampede which occurred when the crowd surged forward toward church officials who were sharing gifts, including foodstuff to participants at the event.
The church, Kings Church Assembly, held the event at the Port Harcourt Polo Club, a facility considered big enough to accommodate the expected crowd.
A statement from a presidential spokesperson, Garba Shehu, on Saturday, said Mr Buhari is "deeply saddened" by the incident.
The statement said the president directed that "all efforts should be made to provide relief to those injured in the unfortunate incident".
Mr Buhari also directed federal relief agencies to work with the Rivers State Government on the incident.
President Buhari, while expressing his condolences and that of the nation to the bereaved families and to the government and people of Rivers State, advised event organisers to plan and carry out their events in a "disciplined manner" to avoid such calamity.
The tragic incident occurred on a day the leading opposition party, the Peoples Democratic Party, is electing its presidential candidate in the nation's capital, Abuja.
The Governor of Rivers State, Nyesom Wike, who is a PDP presidential aspirant, is taking part in the Abuja event.
This is not the first time Port Harcourt has witnessed such a deadly stampede.
Several people were similarly killed in the city in February 2019 during a political rally organised to support President Muhammadu Buhari's campaign for a second term.