It also said consumption of GM maize by livestock could jeopardise Zimbabwe's beef exports to Europe. Government officials were not available for comment yesterday.

"Yes, we do have an indication of preparedness on the part of the Zimbabwe government to accept 20,000 metric tonnes of food. Of that, 17,500 is whole kernel maize and that is where the GM issue comes in," said U.S. spokeswoman Heather Lippitt.

"Any given shipment of maize could contain GM food. When the maize is delivered, will depend on when an agreement on outstanding issues with the government of Zimbabwe can be reached," Lippitt told Reuters.

She could not say what the outstanding issues were.

Last week U.S. Agency for International Development (USAID) official Roger Winter said Zimbabwe had agreed to take 20,000 tonnes of maize that included GMO foods after USAID gave the country an August 1 deadline to take it or lose it.

But he said there was no word on future maize donations and therefore he did not take this to mean a policy about-turn.

Zimbabwe, facing its worst political and economic crisis in 22 years of independence, is at the centre of a devastating food shortage in southern African countries, including Malawi, Zambia, Lesotho, Swaziland and Mozambique.

In June, the U.S. gave Zimbabwe 8,500 tonnes of maize but another 10,000 tonnes was rejected because it did not have a certificate saying it had not been genetically modified.

USAID, through the U.N. World Food Programme, has to date distributed 42,930 tonnes of food aid in Zimbabwe.

Once the bread basket of the southern African region, Zimbabwe now needs food aid after drought and the invasion of white-owned farms since February 2000 slashed staple maize output.

Zimbabwe - where aid agencies say four to six million people need food aid this year - and Malawi have been worst hit by the shortages. Winter said Malawi was willing to take whatever food aid it got because the only concern was to save people.

Agriculture Minister Aleke Banda said yesterday donor countries and agencies had pledged 120,000 metric tonnes of maize, which would arrive in monthly 20,000-tonne consignments.

"This, if it keeps coming, should be enough to feed those desperately in need of relief food," he said.

Some of the food coming into Malawi would be genetically modified, said Ellard Malindi, the chief technical advisor in Malawi's Ministry of Agriculture.

"We are importing GM maize from America because we did not produce enough and we can't source traditional maize in the region since most countries are also facing an acute food shortage," he said yesterday.

(Additional reporting by Alvin Pearson in Malawi).