Members of Jewish Labour Movement say allowing return of former London mayor could damage chances in May elections

Senior Jewish activists have urged Labour’s ruling body not to allow the former London mayor Ken Livingstone back into the party, warning that it could damage the party’s chances in May’s local elections.

Members of the Jewish Labour Movement (JLM), including the MP Luciana Berger, have written privately to the national executive committee to warn of the damage that could be done to the party’s reputation if Livingstone’s suspension is lifted, the Guardian can reveal.

Livingstone was given a two-year suspension by Labour’s disciplinary body after making offensive comments about Adolf Hitler, alleging that he was “supporting Zionism before he went mad”.

Members of JLM, which lobbied hard for Livingstone’s suspension, are understood to fear that the lifting of his suspension, due in April, would seriously damage the party’s reputation in key areas where it hopes to win seats in London council elections.

In particular, Labour is hoping to snatch Barnet council from the Conservatives in May, a borough with a large number of Jewish voters. “If the Labour party is serious about repairing its relationship with the Jewish community, there can be no future for Ken Livingstone in the Labour party,” the letter, sent to all members of Labour’s NEC, reads.

“Mr Livingstone’s readmission to full membership of the party [is] due to take place days before local elections across the country, on the 28 April. Hardworking candidates and activists don’t deserve the indignity of the NEC undermining their efforts to win votes for the Labour party by failing to act.”

It is understood that Livingstone has been the subject of numerous further complaints, which are yet to be investigated, since he was suspended by the party’s national constitutional committee last year. His case is set to be heard by the NEC’s disputes panel next week, who can refer him again to the NCC, the only body with the power to expel a Labour member.

A Labour source said it was wrong to suggest an end to suspension was inevitable, and that it was highly unlikely that Livingstone would be reinstated until those issues were investigated and resolved.

In the letter, the JLM activists highlighted comments by the Labour leader, Jeremy Corbyn, where he said Livingstone had been “grossly insensitive” and had “caused deep offence and hurt to the Jewish community”.

“It is deeply disappointing that, despite his long record of standing up to racism, Ken has failed to acknowledge or apologise for the hurt he has caused. Many people are understandably upset that he has continued to make offensive remarks which could open him to further disciplinary action,” Corbyn told BBC News last year.

The letter says Livingstone had not changed his behaviour during his suspension, calling it “deliberate and offensive behaviour towards the Jewish community”. It highlighted an appearance Livingstone made on Iranian state broadcaster Press TV on Holocaust Memorial Day, where the topic for discussion was: “Has the Holocaust been exploited to oppress others?”

“His appearance was grossly insensitive, and follows the now familiar pattern of deliberate and calculated offensive behaviour. The NEC cannot allow this to continue whilst Ken Livingstone remains a member of the party,” the letter said.

The letters’ signatories include JLM’s national vice-chair, Mike Katz, the party’s 2017 candidate in Hendon, north-west London, and its 2015 candidate in Finchley and Golders Green, Sarah Sackman, both former Labour seats now held by the Conservatives.

Livingstone told the Observer last week that the matter was over and he expected to be reinstated. If he were thrown out, he would take legal action against the party, he said.

The former mayor argued that he had been referring to an agreement between German Zionists and the Nazi government in 1933. “You can’t expel someone for stating historical fact,” he said.