LABOUR’S election campaign has taken a major blow today with an “unprecedented and devastating” intervention by the country’s Chief Rabbi, who claimed Jeremy Corbyn’s handling of anti-Semitism was "incompatible" with British values and made him "unfit for high office".

Ephraim Mirvis said the "overwhelming majority of British Jews are gripped by anxiety" ahead of the December 12 poll and warned: "The very soul of our nation is at stake."

Justin Welby, the Archbishop of Canterbury, also intervened, noting: “That the Chief Rabbi should be compelled to make such an unprecedented statement at this time ought to alert us to the deep sense of insecurity and fear felt by many British Jews.”

Mr Mirvis’s comments will overshadow Labour’s launch of its Race and Faith manifesto in London this morning at which the Labour leader is due to speak.

Labour rejected the Chief Rabbi’s claims. A spokeswoman insisted: “Jeremy Corbyn is a lifelong campaigner against anti-Semitism and has made absolutely clear it has no place in our party and society and that no one who engages in it does so in his name.

“A Labour Government will guarantee the security of the Jewish community, defend and support the Jewish way of life, and combat rising anti-Semitism in our country and across Europe. Our race and faith manifesto, launched today, sets out our policies to achieve this.”

The Opposition has been dogged by accusations of failing to tackle complaints of anti-Semitism quickly enough since Mr Corbyn took charge and numerous MPs have quit the party over the issue.

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Two former Labour MPs have spoken out in support of the Chief Rabbi’s condemnation.

Luciana Berger, who quit Labour in February over the party's alleged anti-Semitic prejudice, said on Twitter: "Unprecedented and devastating intervention from the Chief Rabbi.

"During the last meeting I had with Jeremy Corbyn at the end of 2017 I told him about the many public and private Facebook groups that were littered with anti-Semitic posts which used the Labour leader's name/and photo in their group name.

"Nothing was done about it following our meeting…The party says 'no one who engages in it [anti-Semitism] does so in his name.' But that is exactly what has happened."

Ms Berger is standing as a Liberal Democrat candidate in the north London constituency of Golders Green.

Another former Labour MP, Ian Austin, also spoke in support of the Chief Rabbi.

He said on Twitter: "It is unprecedented for the Chief Rabbi to have to do this. It is heart-breaking to see a party so many of us joined to fight racism and which had such a proud record of fighting for equality reduced to this.

"Utterly shameful. A complete disgrace. Corbyn & co should be so ashamed," declared Mr Austin, who quit Labour in February. He is not running in the election.

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On the campaign trail in Cornwall, Jo Swinson said: "It is hugely worrying that the Chief Rabbi has felt compelled to make such an intervention in an election.

"It speaks volumes about the genuine fear that people in the Jewish community feel about Jeremy Corbyn and his inability to tackle anti-Semitism in the Labour Party.

"All of us whatever our religion, or none, whatever our race, we should take very seriously the concerns of a community within our country that is genuinely feeling unsafe," declared the Liberal Democrat leader.

She added: "And think about what that says about our politics; that that is because of the actions of the leader of a mainstream party."

Meanwhile, Sajid Javid said he was "very saddened" by Mr Mirvis’s comments.

"To think the Chief Rabbi of a European nation has to say this about a contender for high office in 2019. We should all reflect on the state of our politics," tweeted the Shadow Chancellor.

In an article for The Times, Mr Mirvis wrote that the Labour leader's supporters have "hounded parliamentarians, members and even staff out of the party for challenging anti-Jewish racism".

He went on: "The way in which the leadership has dealt with anti-Jewish racism is incompatible with the British values of which we are so proud - of dignity and respect for all people.

“When December 12 arrives, I ask every person to vote with their conscience. Be in no doubt, the very soul of our nation is at stake."

Today, Labour will seek to convince people of its determination to create a more just and equal society with its “ambitious and transformative” Race and Faith Manifesto.

The measures include:

*the creation of an Emancipation Educational Trust to ensure historical injustice, colonialism and role of the British empire is taught in the National Curriculum;

*extend pay gap reporting to BAME groups to tackle pay discrimination based on race;

*establish a Race Equality Unit based within the Treasury which will review major spending announcements for its impact on BAME communities;

*end “rip-off charges” for passports, visas, tests and other documentation imposed by the Home Office;

*launch a wide-ranging review into the under-representation of BAME teachers in schools and

*establish an independent review of far-right extremism which has “seen significant growth over the last few years”.

Ahead of the launch, Mr Corbyn said: “Labour is the party of equality and human rights. Our Race and Faith Manifesto presents our unshakable commitment to challenge the inequalities and discrimination that has faced to many communities.

“Whatever your background, wherever you are from, whatever your faith or religious belief, you should have the chance to use your talents to fulfil your potential. Labour will tackle head on the barriers that have unfairly held back so many people and communities.

“Labour is on your side and this election is a once-in-a-generation chance for real change for the many, not the few," he added.

According to the latest ICM poll of more than 2,000 people conducted between last Friday and Monday the Conservative 10-point lead has fallen to seven with support for the Tories down one point to 41 per cent while Labour was up two points at 34.