Historian David Irving, who is suing a fellow academic for libel, has denied millions of Jews were systematically killed by the Nazis in concentration camp gas chambers.

Mr Irving told the High Court the "gas chambers Holocaust" was "a big lie".

The 62-year-old author of Hitler's War and Goebbels: Mastermind of the Third Reich is suing Professor Deborah Lipstadt and Penguin Books for libel over the "evil" claim in her book, Denying the Holocaust: The Growing Assault on Truth and Memory that he was a "Holocaust denier".

Mr Irving alleges they were part of "an organised international endeavour" to destroy his career and said the "waves of hatred" they had generated had robbed him of financial security for the future.

Prof Lipstadt, holder of the Dorot Chair in Modern Jewish and Holocaust Studies at Emory University in Atlanta, Georgia, and the publishers deny libel and plead justification.

Systematic gassing

Giving evidence on the second day of the libel action, Mr Irving, who lives in Mayfair, London, told Mr Justice Gray the defendants would find it very difficult to suggest the systematic extermination of the Jews "was a Third Reich decision, a Hitler decision".

Asked if he accepted or denied there was any systematic gassing of Jews in concentration camps, at Auschwitz or elsewhere, he said: "If we can leave out the word systematic I do not deny that there was some kind of gassing at Birkenau. It is highly likely that there was."

Cross-examined by Richard Rampton QC, Mr Irving said: "I deny the gas chambers. I deny that the Germans killed millions in gas chambers."

He also denied the killings were carried out in "purpose-built" establishments.

Mr Irving said a million people weighed 100,000 tonnes, presenting a "major logistical problem".

Violent means

He added: "I'm denying that any kind of multiple of millions of people were killed in the gas chambers at Birkenau."

Asked if he accepted the Nazis killed millions by violent means and not just by disease, overwork or starvation, Mr Irving said he did.

He added: "Whether it was in the order of millions or not, I would hesitate to specify. Perhaps one million. Less than four million."

Mr Irving said he had removed the word Holocaust from the second edition of his biography of Hitler because it was imprecise.

He said: "I found it misleading, offensive and untruthful because it's too vague and unscientific, and should be avoided like the plague."

The hearing was adjourned until Thursday.