Due to attacks by militant group Boko Haram that forced farmers to leave their land, an estimated 4.4 million people in northeast Nigeria could face acute hunger, the UN said.
Farmers have been targeted in the insurgency and the army has been carrying out operations against militants.
The area has suffered decades of violence and the UN says this could lead to food insecurity.
The loss of livelihoods because of the coronavirus pandemic has also been cited.
“The authorities in Nigeria should collaborate with NGOs to prevent the food shortage”, the UN’s humanitarian chief in Nigeria Edward Kallon said.