GENEVA - Millions of people across southern Africa are facing the worst food crisis in decades, the World Food Programme (WFP) said on Tuesday, warning that its ability to provide relief risks being stymied by funding shortfalls.

Amid unprecedented drought conditions, a record five countries - Lesotho, Malawi, Namibia, Zambia and Zimbabwe - have declared a state of disaster and called for international humanitarian support, the UN agency said. Angola and Mozambique are also badly affected and around 21 million children are malnourished.

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"Unless we receive additional resources, millions of people risk going through the worst lean season in decades without assistance," WFP spokesperson Tomson Phiri told a Geneva press briefing.

The agency is planning to provide food and, in some cases, cash assistance to more than 6.5 million people in the seven hardest-hit countries to cover the period until the next harvest in March.

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The WFP said, however, that it had only received about a fifth of the $369 million it needed.

"Crops failed, livestock has perished and children are lucky to receive even one meal per day. The situation is dire, and the need for action has never been clearer," said Phiri.