Officials said this month that up to 2 million affected people in the region have not been contacted, "and we can't assess their situation," said U.N. Assistant Secretary-General Toby Lanzer. "We can estimate that it's awful."
Nigerians displaced by Boko Haram now threatened by famine →
With Nigeria in a recession and without speedy outside help, "we will see, I think, a famine unlike any we have ever seen anywhere," he said.
Nigeria facing 'a famine unlike any we have ever seen' →