"We are looking at the possibility of this thing failing," a senior diplomat told our reporter as Mr Mugabe demanded an end to sanctions at the UN General Assembly in New York last night.
Another gave the deal a mere 25 per cent chance of survival, saying Mr Mugabe had entered it in bad faith and duped the opposition leader Morgan Tsvangirai.
Both gave warning of catastrophe if the deal collapsed. One spoke of Zimbabwe’s "final implosion", with "Ethiopian-style" mass starvation and another million desperate people flooding into neighbouring countries.
They said Mr Mugabe believed he could flout the agreement with impunity because the world was distracted: the West was facing economic meltdown, Washington had a presidential election looming, Gordon Brown was fighting for survival and Thabo Mbeki, the former South African President who brokered the deal, had been ousted.
Nearly two weeks after the agreement was signed, to great fanfare, Mr Mugabe’s Zanu (PF) party and Mr Tsvangirai’s Movement for Democratic Change have failed even to agree a division of ministries, with Zanu (PF) demanding every key portfolio.
Mr Tsvangirai told Western officials in Harare yesterday that the MDC had ceded the Defence Ministry, which controls the Army, and the dreaded Central Intelligence Organisation to Mr Mugabe. Zanu (PF) is also demanding the Home Affairs ministry, which would give Mr Mugabe control ofthe police, and the Finance Ministry, which would leave it in charge of Zimbabwe’s devastated economy.
"Zanu wants everything," said one of those present, adding that the officials had urged Mr Tsvangirai to show less trust and "more spine".
Mr Mugabe told the Associated Press that negotiations were continuing during his ten-day stay (with an entourage of 54) in New York, but one of the diplomats denied that.
They accused him of using the same delaying tactics he employed in March, when the regime suppressed the presidential election results for weeks while it worked out how to overturn Mr Tsvangirai’s victory.
Mr Mugabe and his party have shown contempt for the deal from the outset. In a televised speech, the octogenarian President insisted that Zanu (PF) remained in the driving seat and "would not tolerate any nonsense from our new partners".
In a pseudonymous newspaper column George Charamba, his spokesman, insisted Mr Mugabe remained head of state and government, said Zanu (PF) had to learn to govern with "the enemy now within" and spoke of war if the MDC tried to reverse land seizures.
The diplomats said Mr Mugabe was under pressure from his generals, who felt he had sold out. However, one added: "Mugabe was never going to give up power quietly. He wants to die in office."
Zimbabwe’s neighbours in the Southern African Development Community (SADC) have asked Mr Mbeki to continue monitoring the agreement. However, while some observers believe his removal from the presidency has robbed Mr Mugabe of his protector, the diplomats say it has neutered the one man who could have forced Mr Mugabe to honour the deal.
Unless Mr Mugabe cedes real power the West will not give Zimbabwe the billions of dollars it needs to rebuild an economy crippled by inflation running at 40 million per cent, the flight of four million of its citizens, and a desperate food and fuel shortage.
Yesterday Save the Children said that Zimbabwean children were eating rats and inedible roots riddled with toxic parasites to stave off hunger. A diplomat said the Government needed 850,000 tonnes of grain to avert famine but had just 75,000 tonnes left.
Mr Mugabe told Associated Press the West should lift its "demonic" sanctions against his regime, and accused Britain and America of "waiting for a day when this evil man called Robert Mugabe is no longer in control".
Had he thought of resigning? "No — or of dying."