Labour‘s official Jewish affiliate has announced that it will not support the party in the upcoming general election campaign because of Jeremy Corbyn‘s “failure of leadership” over antisemitism.

The Jewish Labour Movement (JLM) said it believed Mr Corbyn was unfit to be prime minister and claimed that “a culture of antisemitism has been allowed to emerge and fester in the party at all levels”.

The organisation, which has been affiliated to Labour for 100 years, said it would only campaign for “exceptional candidates” who had been staunch allies in the fight against antisemitism, such as its own parliamentary chair.

The announcement will come as a blow to Mr Corbyn just a day into the six-week election campaign ahead of the 12 December poll.

During the 2017 election campaign, JLM organised more than 50 campaign events to promote Labour candidates and its members travelled across the country to knock on doors and deliver leaflets.

Protests against Labour antisemitism Show all 14 1 /14 Protests against Labour antisemitism Protests against Labour antisemitism Protesters clashed during the demonstration Reuters Protests against Labour antisemitism Members of the Jewish community hold a protest against Labour party leader Jeremy Corbyn and antisemitism in the Labour Party AFP/Getty Protests against Labour antisemitism Protesters hold placards and flags during a demonstration, organised by the British Board of Jewish Deputies for those who oppose antisemitism, in Parliament Square Reuters Protests against Labour antisemitism Hundreds of people gathered in Parliament Square to protest against antisemitism in the Labour Party EPA Protests against Labour antisemitism Labour MP Luciana Berger speaks during the protest PA Protests against Labour antisemitism A protester blows through a shofar during the demonstration Getty Protests against Labour antisemitism Members of London's Jewish community protest in support of Labour leader Jeremy Corbyn outside parliament EPA Protests against Labour antisemitism Labour MP John Mann speaks during a protest against antisemitism PA Protests against Labour antisemitism People protest against antisemitism in the Labour Party as Jewish community leaders have launched a scathing attack on Jeremy Corbyn, claiming he has sided with antisemites ‘again and again’ PA Protests against Labour antisemitism Labour politicians Stella Creasy and Chuka Umunna leave after attending the demonstration Getty Protests against Labour antisemitism A pro-Jeremy Corbyn protester holds a placard during a counter-protest Getty Protests against Labour antisemitism A support of the Labour Party hold up a placard during the demonstration Reuters Protests against Labour antisemitism Jeremy Corbyn supporters during the demo Reuters Protests against Labour antisemitism A protester holds up a sign reading ‘For the many, not the Jew’ AFP

The group has been highly critical of Mr Corbyn response to antisemitism. At its Annual General Meeting in April, it held a vote on whether to disaffiliate from Labour but members vowed to “stay and fight”, despite declaring that they believed Mr Corbyn was unfit to be prime minister.

Labour is currently being investigated by the Equalities and Human Rights Commission following complaints that it is institutionally antisemitic. While the watchdog is not due to report until January, Mr Corbyn’s handling of the crisis is likely to be brought up frequently by his opponents during the election campaign.

While JLM said it would not campaign for candidates standing against Labour, it is expected to draw attention to Labour MPs who it believes have a poor record of tackling antisemitism.

In a statement, the group said there was “damning evidence of the party’s moral slide” under Mr Corbyn’s leadership and said that “a culture of antisemitism has been allowed to emerge and fester in the party at all levels”.

It said: “This crisis of antisemitism in the Labour Party stems from a failure of leadership from Jeremy Corbyn. When the answer has been to take swift, decisive action, the reality has been equivocation and token gestures. Time and time again, the party has not engaged in good faith to try to implement the actions that we believe are necessary to tackle anti-Jewish racism.

“The disciplinary process has buckled under the weight of antisemitism complaints, and instead of implementing an independent process we’ve seen delay, obfuscation and botched decision making. Political interference is endemic in the system, which is used to protect the leaderships’ friends and allies, rather than ensure the party is a safe space for Jews.”

Describing Mr Corbyn’s leadership as “catastrophic for Jews in the Labour Party”, JLM said it would “not be campaigning unless in exceptional circumstances and for exceptional candidates”, including its parliamentary chair, Stoke-on-Trent North MP Ruth Smeeth, and MPs who had been “unwavering in their support of us”.

It insisted that its position “does not mean we no longer support the Labour Party’s policies and its historic values” but added: “Fighting racism, prejudice and intolerance is at the heart of our Labour values – it is the failure of the leader and his supporters to live these values which has led us to take this stance.”

A Labour spokesperson said: “The Labour Party is fully committed to the support, defence and celebration of the Jewish community and continues to take robust action to root out antisemitism in the party and wider society.

“We have imposed swift suspensions and the rate at which cases have been dealt with has increased more than four-fold. Jeremy Corbyn has made clear that antisemitism has no place in the party, has brought forward reforms to fast-track expulsions, and launched an education programme to deepen understanding of antisemitism within our movement.