South African farmers have demanded Donald Trump "leave us the hell alone" after the US president criticised the country's land reform plans, accusing him of trying to deflect attention from his own scandals.

"The people were furious about Trump -- and I think they still are," said Preline Swart, a 37-year-old black woman who farms grain and cattle with her husband east of Cape Town.

"He's an outsider and he knows nothing about farming," she said on the sidelines of a summit of farmers, officials and industry players in Bela Bela, 100 miles (160 kilometres) northeast of Johannesburg.

Trump's Wednesday tweet, posted on the eve of the "Land Solution" gathering, touched on the overwhelmingly white ownership of farmland in South Africa -- one of the most sensitive issues in the country's post-apartheid history.

"I have asked Secretary of State... (Mike) Pompeo to closely study the South Africa land and farm seizures and expropriations and the large scale killing of farmers," tweeted Trump to his 54 million followers.

His tweet apparently followed a segment on conservative Fox News about Pretoria's plan to change the constitution to speed up expropriation of land without compensation to redress racial imbalances in land ownership.

"'South African Government is now seizing land from white farmers'," said Trump's post, which tagged the show's host, Tucker Carlson, as well as the channel.

"I think Donald Trump must really take his long hair... and leave our people the hell alone," added Swart.

While many of the farmers at Thursday and Friday's land summit rejected Trump's intervention, many are unsure what the government's plan to expropriate land to fix historical injustices will mean for them.

"The deputy president assured farmers government isn't going to do anything reckless," said conference speaker Tshilidzi Matshidzula, 30, a dairy farmer with 1,000 cattle on his ranch in the country's Eastern Cape province.

"(But) as a farmer, although I'm black, expropriation is a serious concern. The sooner we get formal clarity on how it will be handled, the better."

- 'Alarmist, false, inaccurate' -

As he spoke, other black delegates congratulated Matshidzula for the speech he had just given on how to resolve land inequality.

According to President Cyril Ramaphosa, who himself farms cattle on a 5,100 hectare ranch, the white community that makes up eight percent of the population "possess 72 percent of farms".

In contrast, "only four percent" of farms are in the hands of black people who make up four-fifths of the population.

The stark disparity stems from purchases and seizures during the colonial era that were then enshrined in law during apartheid.

"I'm worried about the politicians and the politics in our country if they don't get (land reform) right," said Andre Smith, 49, who grows pecans and other crops on 100 hectares in the Northern Cape province.

"We don't love Donald Trump and his outspokenness."

South Africa's government reacted angrily to the tweet with officials telling their American counterparts Trump's comments were "alarmist, false, inaccurate and misinformed".

- 'Let Donald Trump do his thing' -

"He doesn't understand the South Africa situation. We have to inform him, we have to invite him to visit us," added Smith, overlooking the conference venue's car park, full of the white Toyota pickup trucks beloved of South African farmers.

Trump has a long history of sparking controversy on Twitter.

"Donald Trump was hot-headed -- and not for the first time!," laughed Whiskey Kgabo, a farmer of more than 30 years who grows mangoes on his rented 888-hectare plot in northeastern Limpopo province.

"I don't have anything against Donald Trump... but he should first check that this is the position," said Kgabo who spoke to AFP surrounded by hay bales.

Swart added that Trump, rocked by his longtime lawyer Michael Cohen pleading guilty to felonies and his former campaign chairman Paul Manafort being convicted of federal crimes, "just wants something new to talk about".

Jannie de Villiers, 56, chief executive of the Grain SA industry trade body, rejected the Fox News segment's suggestion that South Africa was following the same path as Zimbabwe's disastrous Robert Mugabe-era seizures of white-owned farms.

"I don't think we're there, and I definitely don't think we're heading for that. It's definitely not the Zimbabwe solution."

Agricultural production collapsed and the economy almost halved in size following the seizures that started in 2000.

"But we do need to address the past and that's not an easy process. We've got a non-racial consensus that we've messed up land reform so far," added De Villiers.

Conference speaker Riedewaan Marcus, 24, a farmer in the Western Cape province backed by the Agri Dwala foundation which supports emerging black agriculture said he was "not a fan of Donald Trump".

"There's a lot going on in America, and there's a lot going on in South Africa," he said. "Let Donald Trump do his thing. And we'll do our thing." (AFP)

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