By Alastair Leithead In Johannesburg

The World Food Programme (WFP) is to renew its call for aid in southern Africa, as famine continues to threaten the lives of millions.

Donations amounting to $30m have already been received since the WFP appealed for a million tonnes of food aid to help combat shortages across the region.

The United Nations agency has warned that 13 million people in southern Africa will need supplies of food over the next nine months, and it is asking again for $500m to help avert disaster.

	Famine crisis: Trail of hunger Zambia's plagues Angola famine Malawi's tragedy Zimbabwe failure Lesotho's needs

Some donations have already been received.

The head of the WFP, James Morris, describes the situation as "the most severe crisis in the world".

The WFP believes the window of opportunity for donations to make an impact is closing, as the crisis is expected to deepen in September.

The call for more donations coincides with a warning from the World Health Organisation.

It says 300,000 people could die of hunger before the end of the year in six African countries - the worst affected being Malawi and Zimbabwe.

Erratic rainfall has been blamed for the food shortages, but political instability and government mismanagement has no doubt contributed to the looming crisis.