The UK Labour Party’s inability to engage with its own Jewish membership has again been thrown into the open as a party affiliate threatens to sue it over a new, softer definition of anti-Semitism.

In an act of open rebellion, Jewish Labour Movement (JLM) chairs Ivor Caplin and Luciana Berger, MP Liverpool Wavertree, have written to members of Labour’s ruling national executive committee, accusing the general secretary, Jennie Formby, of misleading committee members.

The Guardian reports JLM members are outraged that the NEC apparently believed the Jewish activists had approved the Labour version of the anti-Semitism definition.

The new code was rejected as “toothless” by angry campaigners and community groups when it was first released last week and now more groups are saying the code is just not good enough.

They say the code claims it’s not anti-Semitic to compare Israel to Nazis, or smear the Jewish state as racist.

The code states explicitly “anti-Semitism is racism. It is unacceptable in our party and in wider society”, however critics point to the International Holocaust Remembrance Alliance’s (IHRA) working definition of anti-Semitism as a better example for the party to adopt.

It also does not consider as always anti-Semitic claims people are more loyal to Israel than their home country, claims that creating Israel was racist, holding Israel to higher standards than other nations or comparing Israeli politicians to Nazis.

JLC and @BoardofDeputies respond to the new guidelines on antisemitism published by the Labour Party https://t.co/GFGWxnWRo6 pic.twitter.com/m96BxkdML9 — The JLC (@JLC_uk) July 5, 2018

The document does say such actions are “wrong” and specifically warns comparison to Nazis carries a strong risk of breaking the rules.

JLM, the only Jewish group to be an official Labour affiliate, says it is prepared to enter into formal dispute with the party on the matter, which could be followed by legal action.

“It is our understanding that the NEC was informed by the general secretary that the Jewish Labour Movement had approved the three papers on tackling antisemitism that were presented yesterday. You were misled,” a letter seen by the Guardian reads.

“The papers were briefly shown to two JLM representatives over a short informal meeting; there was no pre-sight of the papers or opportunity to read them in full.”

The Simon Wiesenthal Center on Wednesday also denounced Labour’s choice of the definition, saying the party’s refusal to adopt the entire IHRA document was “a slap in the face to the UK’s Jewish community.”

Rabbi Abraham Cooper, associate dean of the Wiesenthal Center said the party’s conduct was “an open invitation to anti-Semites and anti-Jewish activists to find a welcome within England’s political mainstream and has negative implications for world Jewry.”

Board of Deputies President Marie van der Zyl and Jonathan Goldstein, the chairman of the Jewish Leadership Council umbrella group, condemned the new definition in a statement last week.