The abstention by the delegate - New Zealand's Charles Dempsey - allowed Germany to defeat South Africa by a single vote in the contest to host the cup.

I didn't do it lightly. I don't make decisions like that lightly. I was under unsustainable pressure

Charles Dempsey

Scots-born Dempsey had been instructed to back South Africa if England's bid failed.

Fifa spokesman Keith Cooper said Mr Dempsey, 78, had come under "intolerable pressure" ahead of the vote, receiving death threats to himself and his family.

Mr Dempsey has not confirmed the details but, speaking in Singapore on his way home to New Zealand, he said he had been under "unsustainable pressure".

However, he said this was in connection with attempts to bribe him. He said nothing about death threats.

He said he would make a further statement after attending a meeting of the Oceania Football Confederation in Auckland on Sunday.

Threat allegation

New Zealand Prime Minister Helen Clark said she was extremely disappointed by Mr Dempsey's failure to support South Africa's bid.

Charles Dempsey (photo: nzoom.com)

In an interview with the BBC, New Zealand's Minister for Sport Trevor Mallard said Mr Dempsey had made allegations to him about threats, but at this stage details were not clear.

"It doesn't seem logical," he told BBC Radio 5 Live. "We are having trouble understanding why he did what he did."

He said that the whole country was shocked and embarrassed by Mr Dempsey's failure to discharge his responsibilities.

If, as instructed, Mr Dempsey had backed South Africa in the final round of voting, it would have left them tied with Germany on 12 votes apiece.

Fifa president Sepp Blatter would then have had the casting vote - and he was an avowed supporter of the South African bid.

Internal inquiry

Fifa has meanwhile dismissed calls for another vote.

But it said it was opening an internal inquiry into sleaze allegations made in connection with the World Cup bidding.

The German Football Federation and the organising committee are being invited to join in the inquiry.

The inquiry is expected to investigate, among other things, the origin of what is thought to have been a hoax letter sent to a number of delegates, offering gifts if they voted for Germany.

A German satirical magazine, the Titanic, issued a statement on Friday saying it was behind the letter. It said it was meant as a joke.

South Africa's bid committee has meanwhile launched its own investigation into Thursday's decision.

African disquiet

Danny Jordaan, the leader of the South African bid, said he was reserving judgement on the matter.

Zola Zinwar, South Africa's national team manager, has demanded a re-vote and a police investigation.

President Thabo Mbeki described the outcome as a tragedy for the African continent.

"It is a tragic day that their message and ours did not succeed to convince the majority on the Fifa executive that Africa's time has come," Mr Mbeki told reporters.

"Next time we will win," he added.