A recently published book by a former employee of WikiLeaks, Daniel Domscheit-Berg, argues that Julian Assange maintained close ties to a notorious antisemite.

According to Inside WikiLeaks: My time with Julian Assange at the world's most dangerous website, website founder Mr Assange considered giving Israel Shamir, WikiLeaks' representative in Russia, a pseudonym after news reports surfaced of Shamir's antisemitic statements and links to Holocaust deniers.

WikiLeaks is threatening to take legal action against Mr Domscheit-Berg who, it says, "has falsely misrepresented himself in the press as a programmer, computer scientist, security expert, architect, editor, founder, director and spokesman [for WikiLeaks]".

The whistleblower website also denies any collaboration with Shamir. However, this contradicts WikiLeaks' spokesperson Kristinn Hrafnsson's admission on Swedish public radio in December 2010 that Shamir was indeed associated with the website.

Mr Daniel Domscheit-Berg claims that Mr Assange has described Shamir's writing as "compelling" and asked him to collaborate on WikiLeaks. According to Swedish tabloid Expressen, Shamir has set up a support fund for Mr Assange in Moscow and a Russian visa has been prepared for him.

Shamir, a Jew who converted to Christianity and who, according to his website, lives in Jaffa, has said that it is every Muslim's and Christian's duty to deny the Holocaust. He has likened Jews to a "virus in human form" and has expressed admiration for Iranian President Mahmoud Ahmadinejad.

Shamir's son, Swedish journalist Johannes Wahlström, is WikiLeaks' spokesperson in Scandinavia. Mr Wahlström is listed as a "distinguished contributor" on his father's website, which also states that "Shamir-bashing is a popular pastime for supporters of Judaic supremacy on the Web".

Mr Wahlström has been given exclusive access to WikiLeaks cables in Scandinavia and the right to decide who they will be distributed to in the region.

In a 2010 interview on Swedish public radio, Mr Wahlström said he should not be held responsible for his father's opinions and that he disagrees with him on many matters. He complained that "right-wing extremists" were trying to discredit him by linking him to Shamir.

In a 2002 article in Swedish student newspaper Gaudeamus, Mr Wahlström compared Shamir to Noam Chomsky and suggested they had both been dismissed as "self-hating Jews" because of their criticisms of Israel. He said that "Zionism may be a destructive ideology, but not nearly as destructive as 'antisemitism' which crushes all opportunities for free and open debate".

Mr Wahlström was himself accused of antisemitism after writing a story in 2005 for the magazine Ordfront, arguing that "Israel's regime manipulates the Swedish media".