The top American in the UN mission in Afghanistan was fired yesterday after refusing to take part in what he called "a cover-up" of fraud in the Afghan election.

Peter Galbraith, the son of the late economist John Kenneth Galbraith, left the country abruptly last month after a clash with his Norwegian boss, Kai Eide.

Ban Ki Moon, the UN Secretary-General, announced yesterday he was dismissing Mr Galbraith "in the best interest of the mission”.

"I think it's astonishing that the United Nations would dismiss an official because he was concerned about fraud in a UN-funded and UN-supported election," Mr Galbraith told The Times yesterday from his farmhouse in Vermont.

"I want to emphasise that my position was not for or against any candidate. It was simply that the votes should be honestly counted.

"I was not prepared to be complicit in a cover-up or in an effort to downplay the fraud that took place. I felt we had to face squarely the fraud that took place. Kai downplayed the fraud."

The row between Mr Galbraith and Mr Eide goes to the core of international strategy in Afghanistan and has split the UN mission there. Sources said five members of the UN mission in Afghanistan had offered their resignation in support of Mr Galbraith.

Mr Galbraith, a former US ambassador in Croatia, accused his old friend Mr Eide, a former UN representative in Bosnia, of refusing to do anything that jeopardised his relationship with President Karzai.

He said that, before the August 20 election, he wanted to take steps to minimise fraud by eliminating "ghost" polling stations in Taliban-held territory - but Mr Eide rejected the proposal.

During the election, the UN collected data on fraud - but Mr Eide ordered that it not be shared with the Election Complaints Commission, he said.

After the election, Mr Eide objected to Mr Galbraith's insistence that the Independent Election Commission stick to its published anti-fraud criteria, he added.

Nevertheless, Mr Galbraith said that the original row when he left the country had helped push the UN towards a greater focus on fraud.

Preliminary results show Mr Karzai with 54.6 per cent - more than the 50 per cent threshold needed to win re-election without a run-off. An audit of suspect ballots is under way, but UN officials expect the final results to be announced on Wednesday.

Mr Galbraith called the auditing of ballots a "good process" and said it was likely to yield a credible result.

Although a dispute over policy, the row has a personal dimension. Mr Eide introduced Mr Galbraith to the Norwegian anthropologist who became his wife, and the two couples have gone on sailing holidays together off the Dalmatian coast.

Nevertheless, Mr Eide lobbied hard behind the scenes to stop Mr Ban appointing Mr Galbraith as his deputy, but the United States insisted on the appointment.

The row between the two men escalated when Mr Eide left Afghanistan after the election to celebrate his wedding anniversary in Norway with his wife, leaving his deputy in charge.

Sources say a senior American diplomat, Donald "Larry" Sampler, is one of a number of American officials who have been approached to replace Mr Galbraith.

Mr Galbraith is expected to receive one month's pay in lieu of notice and may be entitled to a lump sum "termination indemnity" based on the number of months left on his one-year UN contract, which began in March.

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