A trio of elder statesmen are set to fly in to inspect the situation in Zimbabwe this weekend despite, claims from President Mugabe that they are not welcome and are bent on “illegal regime change”.

Jimmy Carter, the former US President; Kofi Annan, the the former UN secretary-general; and Graca Machel, the wife of Nelson Mandela, are planning a two-day visit to assess the country’s humanitarian catastrophe and to mobilise international help. Zimbabwe is facing several disasters: famine, a cholera epidemic, moribund state and private institutions and inflation measured in the billions.

The trio — members of the Elders, a group of ten respected figures formed to tackle international crises — will be acting in defiance of the Government, which has today issued a warning that they should stay away. It said in an unattributed statement that the trio were “a clique... of personalities hostile to Zimbabwe, a partisan mission by a group of people with partisan interests".

In a coded reference to Western intelligence agencies the statement added: “The Government would want to know whose mission they are representing and who they report to."

Mr Annan issued a counter-statement today to say that he and his colleagues would “make a first-hand assessment of the humanitarian situation in Zimbabwe, to meet those working on the ground, to better assess the extent of the crisis and how assistance can be improved”.

He also said that the trio had sought meetings with political leaders and would be pleased to hear their views, but added that they had “no intention” of being involved with the stalemated attempts to bring Mr Mugabe and Morgan Tsvangirai, leader of the Movement for Democratic Change, to set up a transitional power-sharing government. Diplomatic sources said that their requests for a meeting with Mr Mugabe had been met with silence. “My colleagues and I look forward to our visit,” Mr Annan concluded.

In the past unwanted visitors have simply been turned back at the airport; three years ago a group of top South African trade unionists were arrested and driven 600km (375 miles) back to the border.

The trio’s status may be giving the regime uncomfortable pause for thought, however, as it contemplates the effect on international opinion of kicking them out.

Further pressure was piled on Mr Mugabe today when South Africa said that it would not release nearly $30 million (£20 million)in agricultural aid to Zimbabwe until a new government had been formed there, as it prepares to host new power-sharing talks next week.

The Elders will find a country on the brink of complete collapse. Hundreds of children have starved to death in barely functioning hospitals; almost 300 people have died in a cholera epidemic; and 80 per cent of the population lives in poverty. The only state organisation that was working this week was the riot police who yesterday beat up doctors and nurses protesting at the shortage of drugs and linen for their hospitals.

“This will be a demonstration of how staggeringly mean-spirited, how small-minded and brutally selfish this regime is,” said a Western diplomat. “They really care about nothing except being in absolute control.”

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