A close adviser to Jeremy Corbyn whose daughter is working for the Labour Party on antisemitism complaints dismissed antisemitism claims as a "smear", talkRADIO can reveal.
Andrew Murray, who is a veteran ally of the Labour leader and Chief of Staff at the Unite union, made the comments in 2016.
"We need no lectures from the Conservative government about fighting antisemitism in the Labour movement, and let's also be clear, some people on the right wing of the Labour party are using this issue as the latest stick to beat Jeremy Corbyn with," he said.
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He continued: "They're denying the enormous mandate he won, a mandate in part due to his strong life-long stand against racism and for internationalism.
"And we will not let this disgraceful smear campaign coming from a Tory party which is the real repository of British racism to demonise the Labour party, to smear it of to break our unity."
It emerged yesterday that Mr Murray's daughter, Laura Murray - who currently works in Mr Corbyn's office - has been deputised to provide "administrative support on an interim basis" to a team working on a backlog of antisemitism complaints at party HQ.
It is understood she is not ruling on complaints.
'Greatest crimes of the twentieth century'
In the speech, Mr Murray also said: "Antisemitism was one of the greatest evils and led to the greatest crimes of the 20th century.
"The defence, the full defence, of equality and social and political rights and protection from discrimination and abuse for Jewish people is part of the urgent mandate of our common humanity. There can be no doubt about that and people who play with that with silly phrases and ill-judged comments and bizarre historical analogies are doing us no favours."
A Labour source said: "In this speech in 2016, Andrew Murray said antisemitism led to the greatest crimes of the twentieth century, that it was our urgent mandate to defend against any discrimination or abuse towards Jewish people, and made clear that those in our party who make ill-judged comments are hindering, not helping.
"His comment about some individuals and the Tories' using the issue of antisemitism to attack the Labour Party is clearly true. He did not in any way deny that the problem of antisemitism exists within the party, and he directly confronted it."
A Labour source added: "This speech was in 2016, not in the current context and he would obviously use language differently today."
This morning Labour MP Dame Margaret Hodge claimed Mr Corbyn's office either misled her, or Mr Corbyn had been misled himself, about his team's involvement in dealing with antisemitism cases.
Labour says it is "categorically untrue" to suggest leader's office staff overturned rulings in antisemitism cases.
The Labour Party was contacted for further comment.