A furious row has erupted ahead of a disciplinary hearing to decide whether Ken Livingstone should be expelled from the Labour Party for antisemitism.

Senior hard-left figures have been accused of attempting to influence Labour’s highest disciplinary body ahead of a session expected to decide the former Mayor of London’s fate later this month.

Mr Livingstone has already been served papers after an investigation conducted by the party’s national executive committee (NEC) showing Labour believes he has a case to answer over comments including his claim that Adolf Hitler supported Zionism.

He will now appear before the national constitutional committee (NCC) and attempt to defend himself against possible expulsion.

But at a Labour NEC meeting on Tuesday, concerns were raised about possible attempts to lobby the NCC to adopt a conciliatory tone over the high-profile case.

There is no suggestion Mr Livingstone was aware of the lobbying on his behalf — but moderate NEC members were said to be “fuming” after a GMB union representative attacked a Momentum-aligned fellow NEC member for trying to influence the NCC ahead of the hearing.

Mr Livingstone was suspended from the Labour Party over the Hitler remarks following a ferocious argument with Labour MP John Mann last April.

A Labour insider told the JC: “The idea that an attempt by some members of the hard-left has been made to influence the NCC has infuriated people.

“These are the same voices who shout loudest about enforcing their version of democracy within the party. “Mr Livingstone still remains something of a cult figure among some fringe Labour members. It seems as though some are willing to try anything to stop him from being expelled.

“The membership of the NCC panel in Ken’s case has yet to be finalised. It’s a semi-judicial process so this kind of thing is liable to backfire badly.”

In a recent article on the Left Futures website discussing forthcoming NCC elections, it was stated: “It is of huge importance to the left in the party that we gain control of these bodies, which control the conference agenda and disciplinary procedures, respectively.”

On Tuesday, Labour’s NEC referred the case of former Momentum vice-chair Jackie Walker to the NCC for possible expulsion over comments she made about Holocaust Memorial Day.

Also referred to the disciplinary committee were Marc Wadsworth, a party activist who, at the launch of a report into Labour and antisemitism, challenged Jewish Labour MP Ruth Smeeth claiming she was working “hand-in-hand” with the Daily Telegraph.

Mr Wadsworth said he had not known Ms Smeeth was Jewish and had not intended to offend her at the event.

Labour had suspended Ms Walker in September after she questioned why Holocaust Memorial Day did not recognise other genocides, even though the day is set up to commemorate other atrocities, including those in Rwanda and Bosnia.

After the video of her comments at a Labour conference training event appeared in the media, Ms Walker said whoever leaked the footage “had malicious intent”, and that she was anti-Zionist, not antisemitic.

The activist had previously been suspended from the party after she wrote on Facebook that many Jewish people had been “financiers of the sugar and slave trade”. She was later reinstated.

Jeremy Newmark, Jewish Labour Movement chair, said: “These reported decisions appear to be a step in the right direction and could be a critical move towards the party beginning to turn a corner on this issue. However there is still a long way to go.

“Some of the cases referred to the NCC today date back over a year and should have been concluded a long time ago. Other cases previously referred by the NEC remain unheard by the NCC for many months.

“Meanwhile key promised changes to party rules and processes and the implementation of many of the recommendations from the Royall and Chakrabarti reports remain ‘under discussion’.

“The rhetoric of ‘zero tolerance’ needs to be matched with swift, firm and decisive action against antisemitism.”