Labour MPs voted unanimously Monday night in favour of forcing their parliamentarians to honour the internationally recognised definition of anti-Semitism in the latest move in a row devastating the left-wing party.

Opposition Labour leader Jeremy Corbyn, who has been called both an anti-Semite and a racist by those within his own party, chose not to attend the emergency meeting, delivering more fuel to critics who say he has missed every opportunity to settle the issue since he became leader.

The Parliamentary Labour Party (PLP) unanimously passed the motion to make MPs and peers “accept and abide by” the International Holocaust Remembrance Alliance (IHRA) definition, parts of which were controversially left out of Labour’s new code of conduct.

The matter will not be put to a full ballot of the PLP until Parliament returns from its summer break in September, but the informal vote will further deepen the bitter divide over the party’s mishandling of claims that anti-Semites find a safe home in its ranks.

Jewish Labour lawmaker Margaret Hodge said she was disappointed by Mr. Corbyn’s absence.

“Clearly this is an issue that is totally central to my family and my politics. I think it would have been much, much better if he had been there,” she told the Guardian.

The current crisis in Labour’s ranks was spurred its new code of conduct on anti-Semitism, which features the internationally accepted IHRA definition, but does not replicate in full a list of examples of anti-Semitism published by the IHRA alongside its definition.

UK Labour Jewish Affiliate Ready to Sue over Weak Anti-Semitism Definition https://t.co/bRAqfsa5WG — Breitbart London (@BreitbartLondon) July 12, 2018

The alliance, for example, says it is anti-Semitic to accuse Jewish people of being more loyal to Israel than to their home country, an example not picked up by Labour. The alliance also says it is anti-Semitic to compare contemporary Israeli policies to the policies of the Nazis, a view Labour did not endorse.

Last week the UK’s chief rabbi warned the Labour Party it is sending an “an unprecedented message of contempt” for Britain’s Jews by adopting the code of conduct which claims it is not anti-Semitic to compare Israel to Nazis or to call Israel racist.

Rabbi Mirvis said it was “a watershed moment” for Labour and urged the National Executive Committee — the Labour’s ruling body — to “make the right decision for Britain.”

The anti-Semitism allegations have stalked Labour ever since since socialist Jeremy Corbyn — who called anti-Israeli, anti-Semitic terror groups Hamas and Hezbollah “friends” — was elected party leader.

The suspension of former London Mayor Ken Livingstone for claiming there was “real collaboration” between Zionists and Nazis before the Second World War and MP Naz Shah who was suspended for calling for the “transportation” of Israelis out of the Middle East on social media are just two of the episodes which have captured the public’s attention.