Five countries -- Lesotho, Malawi, Namibia, Zambia, and Zimbabwe -- have declared a state of national disaster in the past months as the drought has destroyed crops and livestock.
Angola and Mozambique are also severely affected, the UN's World Food Programme (WFP) said in a briefing.
The crisis is expected to deepen until the next harvests due in March or April next year, it warned.
"A historic drought -- the worst food crisis yet -- has devastated more than 27 million lives across the region," said the WFP spokesperson for southern Africa, Tomson Phiri.
"Some 21 million children are malnourished."
The WFP is distributing food and supporting relief programmes but has only received one-fifth of the $369 million it requires, Phiri said.
Urgent assistance was required to prevent the drought "deepening into a full-scale humanitarian catastrophe".
The drought has been triggered by the recurring El Nino weather phenomenon, which leads to dry conditions in some regions of the world and excessive rain in others.
A UN official told AFP in July that, according to some estimates, it was the worst drought to hit the region in a century.
It has wiped out 70 percent of the harvest in Zambia and 80 percent in Zimbabwe, WFP's acting regional director for southern Africa, Lola Castro, said.
The lack of rain has also slashed hydropower capacity in the region, leading to major electricity cuts, while Zimbabwe and Namibia have announced wildlife culls to relieve pressure on resources.
Related Links
Climate Science News - Modeling, Mitigation Adaptation
Subscribe Free To Our Daily Newsletters |
Subscribe Free To Our Daily Newsletters |