Malawian President Peter Mutharika on Wednesday declared a state of national disaster due to food shortages caused by drought, in the latest sign of alarm over a hunger crisis across southern Africa.

Zimbabwe, Malawi, Mozambique and Zambia are all suffering food supply problems, while South Africa declared the recent drought its worst in at least 100 years.

“I declare Malawi (in) a state of national disaster following prolonged dry spells during the 2015/16 agriculture season,” Mutharika said in a statement.

“The projected drop in maize harvest is estimated at 12 percent from last year’s output.

“More people will be food insecure and will require humanitarian relief assistance for the whole of the 2016/17 consumption year.”

The World Food Programme said it was currently assisting nearly three million people in Malawi, with about 23 of 28 districts badly affected.