Fresh controversy has erupted over the reputation of the legendary Nazi-hunter, Simon

A new biography of him by Israeli historian Tom Segev was this week dismissed as a "whitewash" by Guy Walters, the British author who challenged Wiesenthal's credibility in his own book Hunting Evil last year.

Mr Walters recently branded Wiesenthal "one of the biggest conmen of the 20th century" for lying about his wartime experiences and exaggerating his role in tracking down war criminals.

He rubbished Dr Segev's explanations for the discrepancies in Wiesenthal's own accounts of his past as "cutesy psychobabble".

Speaking last week on BBC Radio's Today programme, Dr Segev, a well-known columnist with the left-wing Ha'aretz newspaper, said: "Wiesenthal was not a liar. He was a storyteller, a man who lived between reality and fantasy."

He added that Wiesenthal - who died in 2005 - deserved respect because "he did so much to preserve the memory of the Holocaust."

His biography, Simon Wiesenthal: The Life and Legends, includes new material from private papers released by the Israeli government and other archives.

But Mr Walters said: "Segev's new findings don't alter the perspective at all. There is a lot of good stuff in the book. The problem is Segev will use any word apart from 'liar'."

Dr Segev accounted for Wiesenthal's deviations from the truth, Mr Walters said, "as a way of dealing with atrocity… That to me is cutesy psychobabble. There are too many lies for it to be explained away by some sort of survivor guilt."

He admitted that his own judgment on Wiesenthal had hardened since the publication of his book. "Simon Wiesenthal, through claiming to be the hunter of literally 1,100 criminals, made a lot of money on the back of outrageous claims. My feeling is, why go easy on the guy?"

One of the differences between the two authors is over whether Wiesenthal could claim any credit for tracing the German war criminal Adolf Eichmann, kidnapped by Israeli agents in Argentina in 1960.

Dr Segev argues that, in a letter in 1954, Wiesenthal tipped off the Israeli consul in Vienna that Eichmann was hiding in the Latin American country.

But Mr Walters, who has not seen the letter but intends to travel to Austria to examine it, said that Dr Segev had ignored a subsequent letter from Wiesenthal in 1959 saying that Eichmann was probably in Germany.

Dr Segev was unavailable for comment.

Ben Barkow, director of the Wiener Library in London, who has read both books, thought Mr Walters's views were a "harsh judgment", while Dr Segev had "missed an opportunity" to analyse Wiesenthal's character and motives.

He commented: "The truth about Simon Wiesenthal and why he acted the way he did has yet to be told."