Mr Guterres was initially scheduled to travel to the town of Banki, near the Cameroonian border, to meet victims of the Boko Haram insurgency to highlight the humanitarian crisis in the region. But officials say that trip has now been cancelled. 

Instead, Mr Guterres is meeting victims of the conflict in the city of Maiduguri as well as former Boko Haram militants who have laid down their arms, renounced violence and surrendered to the Nigerian authorities. 

It’s not exactly clear why his visit to Banki was cancelled. 

But a spokesperson for the Borno state governor told the BBC the decision was taken due to what he called "some circumstances" without giving details. 

The insurgency which began in 2009 has killed nearly 350,000 people and displaced millions of others in Nigeria, Niger, Cameroon and Chad according to the UN.

Mr Guterres earlier said the humanitarian crisis in the region required more international support to tackle. He also called for more military assistance to Niger, including equipment and finance to enable it to deal with the various extremist groups.

On Wednesday, the UN chief will be meeting Nigerian President Muhammadu Buhari and other senior officials in Abuja as well as youth and women groups.