Labour general secretary Jennie Formby is under fresh pressure to tackle anti-semitism in the party amid claims that she and Len McCluskey failed to call out a union activist who spread claims of a ‘Jewish mafia’.

Former Barnet councillor and Unite member Alon Or-bach told HuffPost that he had been “disappointed” that neither Formby nor McCluskey had condemned publicly an anti-semitic tweet during the union’s general secretary leadership race.

At the height of the bitter battle, an online Twitter account titled ‘1UnionBloke’ posted a message that McCluskey challenger Gerard Coyne was getting backing from Jewish sources.

The tweet was accompanied by an anti-semitic slogan and image.

When Or-bach protested about the image, he was sent a private message by Formby pointing out Unite had supported his candidacy for a Parliamentary seat in Finchley and Golders Green.

HuffPost has obtained screenshots of her direct messages that followed, which show her strong support for McCluskey and her belief that anti-semitism was not a problem within the Unite union. “There’s never been any issue of anti-semitism in Unite,” she writes.

She stressed that the account was anonymous and did not ‘in any way reflect what Len stands for’. 

Formby, a Unite official at the time, urged Or-bach to inform her of specific allegations of abuse and insisted the union was actively working on political education to stamp out ignorance about the issue.

Formby added that the union was firm that it “always encourages people to call out any ignorance (which it usually is rather than deliberate and conscious anti-semitism) whenever it occurs, although of course the tweet from ‘Unionbloke’ was deeply unpleasant and doesn’t come into that category”.

The ‘1UnionBloke’ account was deleted a day later, to which Formby reacted swiftly by saying ‘good riddance’.

Formby, who was due to meet the Jewish Labour Movement on Thursday, has been tasked by Jeremy Corbyn with making the fight against anti-semitism her ‘number one priority’.

Or-bach, who stood down from Barnet council last week, told HuffPost that he had not gone public about Formby’s remarks until now because he didn’t want to be seen harming the party’s chances in the local elections.

“I raised this tweet because I would have expected it to be called out. I was somewhat taken aback by the direct approach I got, rather than saying we condemn this, this is nothing to do with us, she seemed to be basically saying flagging it was unhelpful to Len,” he said.

“The complete dismissal of any anti-semitism within Unite I found bewildering. Instead, Unite should have been trying to track this guy down, and with IP addresses there are ways to find out who these trolls are. Was he a Unite member and was any disciplinary action taken?”

Or-bach said that he had been prompted to speak out after he’d seen Shadow Equalities Minister Dawn Butler claim that the real reason for the delays in tackling anti-semitism were down to former general secretary Iain McNicol.

“I found that sickening. Iain McNicol and his staff did an amazing job in difficult times. He didn’t have the support of the leader’s office and if he had we could have dealt with anti-semitism cases in a swift manner.

“It’s pretty obvious that the leader’s office and others kept pushing back against what they saw as ‘purges’. That’s what’s broken me this week, this idea that Labour party staff are being made scapegoats for the lack of action. I find that abhorrent.”

Or-bach said that he had decided not to stand again in Barnet because “I can’t cope with this kind of behaviour” and the influence of alt-left websites that portrayed anti-semitism as an attack on Corbyn.

“It’s just too painful and I want to be able to speak my mind, and holding public office made that difficult. The anti-semitism problem is just a lightning rod for the wider conspiracy theory problem taking over the party, with these stupid attacks on the BBC and other media.”

The Labour party has been approached for comment on behalf of Formby.

A spokesman for Unite said: “Len McCluskey was not aware of these comments.  Had he been so he would have had no hesitation in denouncing them.  Len is a life-long campaigner against such abuses and will not tolerate them from any quarter.”

McCluskey was come under attack for previous suggestions that Labour MPs and others had used anti-semitism