Jonathan Arkush, the president of the Board of Deputies of British Jews, today blasted Jeremy Corbyn's response to the row as 'deeply disturbing'

Jeremy Corbyn was slammed by a leader of British Jews today for defending his brother's 'belittling' of anti-Semitism.

Jonathan Arkush, the president of the Board of Deputies of British Jews, said the response of the Labour leader was 'deeply disturbing'.

The intervention represents a new escalation in a growing row within Labour about alleged anti-Semitism among some new members.

Labour MP Louise Ellman has come under anti-Semitic attack in her Liverpool Riverside constituency and joined calls on the Labour leader to do more to tackle anti-Semitism in the party's ranks.

But the demand prompted Piers Corbyn to tweet: 'ABSURD! JC+ All Corbyns are committed Anti Nazi. Zionists can't cope with anyone supporting rights for Palestine.'

In response, Mr Corbyn told The Sun his brother 'isn't wrong', adding: 'My brother has his point of view, I have mine and we actually fundamentally agree - we are a family that were brought up fighting racism from the day we were born.'

Mr Arkush rejected the statement today.

He said: 'Jeremy Corbyn's defence of his brother's belittling of the problem of anti-Semitism is deeply disturbing.

'We cannot imagine that any other minority's concerns would be dismissed off-hand in this way.

'In the last few weeks we have witnessed a stream of clear-cut cases of anti-Semitism in the Labour Party, which can't just be fobbed off as differences over Israel.

'Most of the Jewish community, numerous Labour MPs, Labour peers, and Labour's London mayoral candidate are crying out for the leader to take action on anti-Semitism.

'It would be incomprehensible for Mr Corbyn to remain inert and refuse to take this form of racism in his party seriously.'

Speaking at a campaign visit in Norwich, Mr Corbyn said: 'If anyone reports any form of anti-Semitism within our party, it is investigated immediately and cracked down upon.

'That message is unequivocal - we are a multi-faith, multicultural Britain - let's respect each other and move on from there.'

A Labour spokesman earlier insisted: 'It is Jeremy Corbyn who is taking action on anti-Semitism.

'He has consistently condemned anti-Semitism and all forms of racism and under Jeremy Corbyn's leadership, Labour is clamping down on anti-Semitism and taking clear action against offenders.'

Ms Ellman had used a Sky News interview to call for stronger action on anti-Semitism by the Labour leader.

She said: 'Most members of the Labour party are not anti-Semitic but some are and some are being allowed to get away with posting anti-Semitic comments in tweets and on their websites.'

She added: 'The leader has spoken out clearly, he says he is against anti-Semitism.

'But it's not just about words – there has got to be some action and we haven't seen enough of that.'

Piers Corbyn, the Labour leader's brother, triggered the latest row by branding reports about anti-Semitic attacks on a Labour MP as 'aburd'

Labour MP John Mann today demanded Labour 'sort out our own backyard' and warned the row would be a 'test' of Mr Corbyn's leadership

Sadiq Khan yesterday admitted he wears a 'badge of shame' because of the problems the Labour Party has with anti-Semitism.

The London Mayor candidate said Mr Corbyn 'could have taken a tougher stance and needs to take a tougher stance'.

The party has been dragged into a series of rows about anti-Semitic members which some MPs have warned are not being kicked out of the party swiftly enough.

Jewish Labour MPs have also claimed they have come under attack from anti-Semitic individuals online.

The Labour leader's brother, Piers Corbyn, pictured, sparked the latest anti-Semitism row after he blasted reports about attacks on Louise Ellman as 'absurd'

Mr Khan, a Muslim, said he knew what it was to suffer 'hate crime' and added: 'I also know it's unacceptable in 2016 that there is anti-Semitism in the Labour party.

'It's with sorrow that I wear that badge of shame.'

Mr Khan added: 'If it means members of my party, senior members of my party including members of [Labour's ruling National Executive Committee] being trained about what anti-Semitism is, then so be it.'

Speaking at a hustings organised by the London Jewish Forum, Mr Khan said: 'I have said at the outset, I'm embarrassed and sorrowful about anti-Semitism in the party.

'I think the Labour leadership could have taken a tougher stance and needs to take a tougher stance.'