"There could be some 300 whites back on farms by the end of next year," government land adviser Sam Moyo told the Guardian. "Most of them will be running commercial farms."

Since November, 19 white farmers who lost ownership of their land have been granted 99-year government-backed leases on resettled farms in a spectacular U-turn by Mr Mugabe.

On a commercial farm lying off a clay-dirt road just outside the town of Kadoma, 74 miles from the capital Harare, Jim Boethe described how he had been invited back to his land.

"When land-reform started we had nearly 1,000 hectares growing maize," he said. "It was divided up [by the government] and now we only have 100. But we are happy to be back - we applied for the lease and are waiting for it to be signed."

In July 2005 Mr Mugabe declared that his land reform policy would be complete only when there was "not a single white on the farms". But a contracting economy, hyperinflation touching 1,100% and food shortages have forced the authorities to allow some interested whites to return.

"We had to demonstrate to the government that we were going to be productive, such as growing food for local markets and not just for export. We grow maize, sweet potatoes and tomatoes and export our paprika," Mr Boethe explained.

The land minister, Flora Buka, said the government had received more than 200 applications so far from whites to take up farming again. There are only about 600 white farmers left in Zimbabwe, down from 4,500 six years ago.

After Mr Mugabe was defeated in a referendum on Zimbabwe's constitution in 1999 the government decided to "fast-track" land reform to win over a hostile electorate, resulting in farm seizures by supporters of the ruling Zanu-PF party spearheaded by landless veterans of the country's war for independence.

The UN-funded World Food Programme has said that two million Zimbabweans will need food aid in the next six months despite improved agricultural output last season.

But welcoming back white farmers might be too little too late.

"We know other farmers that have gone elsewhere - Australia, South Africa, even Nigeria. We looked at a farm in neighbouring Zambia too, just to keep our options open," said Mr Boethe. "People have very little foreign exchange to buy inputs now - so a lot of the land is just idle."

Critics say the new 99-year leases won't do much to boost productivity and, given recent farm appropriations by government, farmers will be reluctant to invest.

The government is more bullish, arguing that now land reform has been consolidated - with some 150,000 people resettled on farms according to official figures - yields will begin to increase.

But the move comes amidst deepening crisis in the country as Mr Mugabe has announced plans to "harmonise" presidential elections - scheduled for 2008 - with the parliamentary poll in 2010. The government says the plan will save money, but critics say it is the first move to prolonging his rule indefinitely - fears that were fuelled when land minister Didymus Mutasa recently suggested Mr Mugabe should be made president for life.

The proposal has infuriated Zanu moderates who were hoping Mr Mugabe would retire and give a new government a chance to rebuild bridges with western donors who have suspended aid.

The proposal has also inflamed a succession struggle following Mr Mugabe's decision in 2004 to appoint Joyce Mujuru, a relative political lightweight, as his deputy - a post seen as a stepping stone for the top job. Ms Mujuru, who owns several farms, is jostling against the rural housing minister Emmerson Mnangagwa for Mr Mugabe's blessing.