Oxfam calls the level of inequality in the country "obscene." The disparity is only growing, the charity says, in light of what it describes as the misallocation of the country's resources.
But officials offered no further clarity on the illness that has repeatedly sidelined Muhammadu Buhari this year. In announcing the visit, a spokesman merely stated that "there is no cause for worry."
Nigerians are raising concerns about the health of Muhammadu Buhari, who hasn't been seen in public for more than a week and has missed his third straight cabinet meeting.
Nomadic herders who live across West Africa are having to travel further and further south for their cows to graze. Some are letting cows graze on cropland, leading to deadly conflicts with farmers.
Conflict and drought have ravaged four countries across North Africa and the Middle East, leaving more than 20 million people in desperate need of food.