The South African government has told white farmers that they risk losing their farms if they fail to agree a selling price within six months
The Agriculture and Land Affairs Minister, Lulu Xingwana, said the deadline was necessary to speed up the transfer of farms to black people who were forcibly removed from their land under apartheid.
The transfers are part of a government programme to get 30% of farmland in black hands by 2014.
Land reform is one of the most emotive and politically charged issues in South Africa.
And returning land seized from black farmers during apartheid was one of the key promises made by the African National Congress when it came to power in 1994.
More than 10 years on, only 4% of land has been transferred and the government is under fire for going too slowly.
The problem, ministers say, is that it is taking too long to negotiate with white farmers over the price of land.
Now, for the first time, the government has set a time limit on talks - it will negotiate for six months and no more. After that, land could be expropriated.
The challenge for the ruling ANC is to keep the promises it has made while avoiding the violence that has surrounded land reform in neighbouring Zimbabwe - where it helped bring about the collapse of the country's highly profitable agricultural sector.
But it is a hugely complex process.
One problem is sorting out competing claims over the same piece of land.
Families removed from farms generations ago often do not have documents. Family trees have to be constructed to see who is entitled to a share.
And if black farmers are allocated land, but not given enough capital to develop it, then agricultural production could fall.
But whatever the short-term costs, advocates of land reform say the longer-term risks of political instability are much higher if the issue is not tackled faster.
Already, grievances over land have led to violence in some areas.
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