Jeremy Corbyn has been accused by a former leader of Scottish Labour of an “arrogant” and “inept” handling of the row over anti-Semitism.
Former Cabinet minister Jim Murphy took out a full-page advert in the Glasgow edition of the Jewish Telegraph to offer an apology to British Jews and to accuse Mr Corbyn of failing to do enough to throw anti-Semites out of his party.
It came as the Labour leader faced fresh criticism after footage emerged of him drawing comparisons between the Nazi occupation of wartime Europe and Israeli actions in the West Bank.
And the leader of Britain’s biggest public service union – and major Labour donor – Unison, Dave Prentis, added his voice to calls for the party to adopt in full the International Holocaust Remembrance Alliance definition of anti-Semitism, including its list of examples of prejudicial behaviours.
Mr Murphy said that under Mr Corbyn, Labour appeared to have “deliberately turned its back on British Jewry”.
“It’s as inexplicable as it is destructive,” he said.
“And when in a hole of its own making, rather than stopping digging, Labour’s leadership has asked for a bigger shovel.
“British Labour’s top team has shown itself to be intellectually arrogant, emotionally inept and politically maladroit.”
Mr Murphy, who was a minister under Tony Blair and Gordon Brown and led Scottish Labour from 2014-15, said there was “a small, but growing minority, of antisemitic conspiracy theorists amongst the membership of the Labour Party”.
And he said: “Jeremy Corbyn is not doing nearly enough to throw out the anti-Semites found within grassroots and online Labour.”
Mr Murphy’s dramatic intervention increases pressure on Mr Corbyn and Labour’s National Executive Committee to reconsider the code of conduct on anti-Semitism agreed last month, which omits four of the IHRA examples from its own list of unacceptable behaviours.
Labour argues that the items – mostly dealing with criticisms of the state of Israel – are covered elsewhere in the document in a way which will make it easier to take disciplinary action.
But senior figures including deputy leader Tom Watson have said the IHRA text should be adopted in full, and MPs are expected to back this stance in a vote in September.
Writing on the New Statesman website, Mr Prentis said that “adopting the full IHRA definition of anti-Semitism including all the examples, removing those guilty of racism from our party and putting the issue of Labour and anti-Semitism to bed as quickly as possible” was “critical” to the party’s efforts to win power at the next election.
The issue was costing Labour votes and harming its relationship with the Jewish community, said Mr Prentis.
But he added: “It isn’t too late for the party to chart a different course and begin repairing that damage, as Jeremy Corbyn is clearly attempting to do.
“Anti-Semitism in Labour didn’t start under Jeremy, but I am confident that under his leadership it can be dealt with once and for all.”
Meanwhile, an anonymous Twitter feed called The Golem published video of Mr Corbyn in 2013, discussing the occupation of Palestinian territories in the context of the Second World War.
“The Palestinian people are generally very poor and in the case of Gaza, virtually imprisoned within that very small area and facing environmental disaster and catastrophe,” said Mr Corbyn.
“And in the West Bank, under occupation of the very sort that would be recognised by many people in Europe who suffered occupation during the Second World War, with the endless road blocks, imprisonment, irrational behaviour by the military and the police.”
One of the examples of anti-Semitic behaviour removed by Labour from the IHRA list was the act of comparing contemporary Israeli policies with those of the Nazis.
Labour Friends of Israel, which campaigns for a two-state solution, called the comments “appalling”.
But the Labour Party insisted Mr Corbyn was not comparing the Israeli State with the Hitler regime.
A spokesman said: “Jeremy was describing conditions of occupations in World War Two in Europe, of which there are multiple examples, not comparing the Israeli State to Nazis.”
It comes after the account tweeted footage earlier in the week showing Mr Corbyn appearing to query the right of Israel to exist.
Jennifer Gerber, director of Labour Friends of Israel, said: “Earlier this week, we discovered that Jeremy Corbyn engaged in wild conspiracy theories questioning Israel’s right to exist.
“Today, it is revealed he drew comparisons between conditions in the West Bank and the Nazi occupation of Europe.
“It is increasingly clear that his opposition to adopting the IHRA definition in full appears to be overwhelmingly driven by his own appalling past statements.
“The Labour party’s once proud record on fighting racism and the protection of British Jews from anti-Semitism is being sacrificed to protect Jeremy Corbyn’s reputation.”
Jewish leaders earlier urged Mr Corbyn to “come out of hiding” and address the anti-Semitism issue.
Labour has declined to set out the party leader’s holiday plans but Mr Corbyn was pictured in The Sun apparently enjoying a summer break in Somerset.
In an article for the Jewish News, the president of the Board of Deputies of British Jews Marie van der Zyl wrote: “He is clearly just hoping it will go away. I’ve got some bad news for him – unless he does what he needs to do, it won’t.”