Tom Watson has broken ranks with Jeremy Corbyn, to warn Labour faces being lost in a “vortex of eternal shame” unless it deals with concerns over anti-Semitism in the party.
And he called on the party to drop disciplinary action against two senior MPs.
In a stark message, Mr Watson said Labour had to take a “long, hard look at ourselves” and demanded immediate action to end tensions, including fully adopting an international definition of anti-Semitism which the party’s ruling body has so far resisted.
Meanwhile, the Jewish Leadership Council and Board of Deputies rejected Jeremy Corbyn’s latest attempt to calm tensions over the anti-Semitism row.
They accused the Labour leader of “ideological hostility” to the International Holocaust Remembrance Alliance (IHRA) definition of anti-Semitism and its 11 examples.
Mr Corbyn has said that seven of the examples have been fully adopted in Labour’s code of conduct, with “the essence” of the other four captured in the document.
But he said there was an an issue about “half of one example out of 11” because it could restrict criticism of Israel.
“It is unfortunately the case that this particular example, dealing with Israel and racism, has sometimes been used by those wanting to restrict criticism of Israel that is not anti-Semitic,” he claimed.
But in a joint statement following his comments – a response delayed because the Labour leader’s “ill-timed and ill-conceived” Guardian article was published on Friday night as Jews observed the Sabbath – the Jewish Leadership Council and Board of Deputies criticised his approach.
They claimed the abuse suffered by their community “whether you call this anti-Semitic or not” had resulted in “Jews and those who support them… being purged out of the party”.
“Above all, however, Mr Corbyn’s ideological hostility to the IHRA definition of anti-Semitism epitomises the enduring problem.
“His article falsely claimed that Labour’s new code only sought to alter one part of the definition.
“As can be plainly seen, the code alters and relegates four parts that say it may be anti-Semitic to: 1. Accuse Jews of disloyalty, 2. Compare Israel to Nazi Germany, 3. Hold Israel to unique standards and 4. Call a Jewish State racist.
“It is quite obvious why Jeremy Corbyn and (Labour communications chief) Seumas Milne are so anxious to diminish these parts of the IHRA definition.”
They added that “actions are the only thing that have ever mattered” but claimed Mr Corbyn was merely restating words he had already used.
“None of the cliches and promises have been met, the hatred and vilification has intensified and the purging is now gathering pace.
“These are the actions that should matter, not just to Jews, but to all decent people who believe in fundamental liberal democratic principles.”
Mr Watson said the party should fully adopt the IHRA definition.
In a strongly worded intervention, Mr Watson told the Observer: “This is one of those moments when we have to take a long, hard look at ourselves, stand up for what is right and present the party as fit to lead the nation – or disappear into a vortex of eternal shame and embarrassment.”
He called for disciplinary action against MPs Ian Austin and Dame Margaret Hodge – who confronted Mr Corbyn in Parliament over his response to the row – to be dropped.
“I think it is very important that we all work to de-escalate this disagreement, and I think it starts with dropping the investigations into Margaret Hodge and Ian Austin,” he said.
“I have frequently had very difficult conversations with both Margaret and Ian but what I understand is that your critics are not your enemies. On an issue that is so dear to them, I think people are very, very concerned that these investigations should be dropped quickly.”
He added: “We should deal with this swiftly and move on. We can’t have this dragging on throughout the summer.
“I have made no secret of the fact that… we should adopt the full IHRA definition and should do it without delay.”
Meanwhile, shadow chancellor John McDonnell was forced to distance himself from the anti-Semitism row over his links with the Labour Representation Committee (LRC) campaign group.
The Sunday Telegraph reported that the group, of which Mr McDonnell is president, said it was “factually true” to describe Jewish critics as “Trump fanatics making up duff information without any evidence at all”, highlighting comments made by former Board of Deputies president Jonathan Arkush in support of the US president.
A Labour spokesman said: “John has no day-to-day involvement in the operation of the LRC and is not responsible for its website or for posts on social media by its supporters.”