Labour is facing calls to suspend a member of its ruling body after he was recorded calling some members of the Jewish community "Trump fanatics".
Peter Willsman was described as a "loud-mouthed bully" by Labour's deputy leader Tom Watson, while Jewish Labour Movement chairwoman Luciana Berger said the recording was "sickening".
The veteran left-winger said he "deeply apologised" for any offence caused by the comments, but said that not all of what he said had been "accurately reported".
The recording's emergence comes amid a flare-up of a row over Jeremy Corbyn's handling of anti-Semitism by some members of the party.
In the clip acquired by the Jewish Chronicle, Mr Willsman can be heard saying with a raised voice: "Some of these people in the Jewish community support Trump - they are Trump fanatics and all the rest of it.
"So I am not going to be lectured to by Trump fanatics making up information without any evidence at all.
"So I think we should ask the 70 rabbis, 'Where is your evidence of severe and widespread anti-Semitism in this party?'"
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In an open letter earlier this month, 68 rabbis called on Labour to adopt the full International Holocaust Remembrance Alliance (IHRA) definition of anti-Semitism, including its examples.
They said anti-Semitism within "sections of the Labour party" had become "so severe and widespread that we must speak out with one Jewish voice".
Labour's governing body, the National Executive Committee (NEC), did not include within its new code of conduct the full definition of anti-Semitism - including illustrative examples - set out by the IHRA.
Ms Berger told the Jewish Chronicle that Labour should suspend Mr Willsman and conduct a "formal investigation".
She wrote on Twitter: "The fact that it took place in a meeting of @UKLabour's sovereign body the other week after all that's happened is a disgrace.
"Blaming any other minority group [wouldn't] be tolerated - why is the Jewish community treated this way?"
Mr Watson tweeted: "For the avoidance of doubt: Peter Willsman is and always has been a loud mouthed bully. He disgusts me."
Mr Willsman, who sits on the NEC, said: "I deeply apologise for any offence caused to those present and those to whom my remarks were reported."
"Not all of what I said has been accurately reported," he told the BBC.
"But I accept that what I did say, and the way I said it, fell short of the requirement, which I accept, for discussions of contentious issues to be conducted in a fully civil and respectful way."