A Labour peer is set to resign in protest at Jeremy Corbyn’s re-election as party leader over his handling of alleged anti-Semitism among some members.

Lord Mitchell, who is Jewish, previously branded an inquiry launched by Mr Corbyn earlier this year a “whitewash” and vowed to quit the party if he won he leadership contest.

The businessman, who was awarded a life peerage in 2000, said he would make a formal announcement on Sunday but signalled he would stick to his decision.

Jeremy Corbyn's campaign team tackle accusations of antisemitism

He accused Mr Corbyn of allowing anti-Semitism to “fester at the highest level of our party” in the wake of an inquiry by Baroness Chakrabarti, who was controversially made a Labour peer within weeks of her report.

While concluding that the party was “not overrun by anti-Semitism, Islamophobia or other forms of racism”, it said hate displaced by a “minority” of members had no place and recommended new sanctions for officials.

The inquiry followed controversy over a Facebook post by Naz Shah, the Labour MP for Bradford West, claims by Ken Livingstone that Adolf Hitler supporter Zionism and a wave of Labour suspensions.

But it was itself beset by controversy after Mr Corbyn compared Israel to “Islamic states” at a launch event, where a Jewish MP left in tears after being heckled.

In a letter to The Times in August, Lord Mitchell called Baroness Chakrabarti’s report an “insipid whitewash”.

Jeremy Corbyn meets with Rabbi Pinter after delivering a speech on Labour's anti-Semitism inquiry findings (PA)

"I have come to the painful conclusion that were Mr Corbyn re-elected...I will have to resign my membership of the Labour Party,” he added.

"As a Jew, I find the allegations of antisemitism in the Labour Party very distressing.

"Even more upsetting is the way Jeremy Corbyn dismisses what he has permitted to fester at the highest levels of our party.

"I cannot remain a member of a party that goes against such a crucual issue that I hold dear."

Following Mr Corbyn's re-election, Lord Mitchell said he was a “man of his word”.

He was not the only Jewish Labour member voicing outrage - one woman posted a photo of her cut up membership card online and announced she was joining the Jewish Labour Movement instead.

Labour antisemitism row: What Livingstone said Show all 14 1 /14 Labour antisemitism row: What Livingstone said Labour antisemitism row: What Livingstone said On Israel and Palestine The simple fact in all of this is that Naz made these comments at a time when there was another brutal Israeli attack on the Palestinians; and there’s one stark fact that virtually no one in the British media ever reports, in almost all these conflicts the death toll is usually between 60 and 100 Palestinians killed for every Israeli. Now, any other country doing that would be accused of war crimes but it’s like we have a double standard about the policies of the Israeli government Labour antisemitism row: What Livingstone said On Antisemitism in the Labour Party As I’ve said, I’ve never heard anybody say anything antisemitism-Semitic, but there’s been a very well-orchestrated campaign by the Israel lobby to smear anybody who criticises Israeli policy as antisemitic. I had to put up with 35 years of this Labour antisemitism row: What Livingstone said On Naz Shah It’s completely over-the-top and rude, but who am I to denounce anyone with all of that. It was wrong. I don’t think she is antisemitic, it was incredibly rude but I don’t believe she is an antisemite. When the NEC investigation is finished they'll say it was rude and over the top but they won’t find any evidence that she actually hates Jews. We’ve got to investigate all these charges and the context in which they are made. If she is antisemitic like the other three or four members we’ve found who are antisemitic, she’ll be expelled Labour antisemitism row: What Livingstone said On other alleged antisemites in Labour That is part of the classic antisemitic thing about an ‘international Jewish conspiracy’ – that is the reason we need to have an investigation. I’ve got an open mind. I’ve seen nothing to suggest to me that she is antisemitic. I wouldn’t have supported her if I [thought] she was antisemitic Labour antisemitism row: What Livingstone said On whether what Hitler did was legal, as stated by Naz Shah That’s a statement of fact – Hitler, I’m sure, passed all those laws that allowed him to do that … it’s history … literally, Hitler was completely mad, he killed six million Jews. She’s not saying it’s legal to kill six million Jews: what they were doing in that country allowed them not just to kill six million Jews, kill all the communists, kill all the leftists like me, my father almost died when a Nazi sub sank his boat. I have no sympathy with Hitler Labour antisemitism row: What Livingstone said On another alleged antisemite in Labour No, that is, and that’s why she’s been suspended or expelled. What I’ve said is that in 47 years of the party in all the meetings I’ve been in I’ve never heard anyone say anything antisemitic. There are bound to be in a party of half a million people you’ll have a handful of antisemites, you’ll have a handful of racists. You’ve managed to dig out virtually every antisemitic comment that Labour members have made out of half a million people. I’ve never met any of these people. There’s not a problem. You’re talking about a handful of people in a party of half a million people. Jeremy Corbyn has moved rapidly to deal with them Labour antisemitism row: What Livingstone said On Jeremy Corbyn’s response to the allegations He met with Naz and she agreed she would stand down while the investigation is going on. He called her in to see her. There’s been a huge investigation of virtually everything that anybody put on the internet … many of these people are quite new and recent members of the party that joined in the big influx. 300,000 new people came in Labour antisemitism row: What Livingstone said On his meeting a man accused of antisemitism in London This is the man who called for Muslims around the world to donate blood after the attacks of 9/11 when he came to London I went with him to the Regent’s Park mosque where he said no man should hit a woman and you should not discriminate against homosexuals. So I can’t equate what I heard him say… he made no antisemitic statement while he was here in London. I don’t investigate people. I’ve simply said what I believe to be true which is that Naz was not antisemitic. She was completely over the top, very rude, but that does not make her an antisemite Labour antisemitism row: What Livingstone said On John Mann’s comments He went completely over the top. I was actually doing a radio interview at the time that he was bellowing that I’m a racist antisemite in my ear. I’ve had that with John Mann before a few weeks ago screaming that I was a bigot down the phone. I’m not an apologist for anyone who makes antisemitic statements. What I’m saying is don’t confuse antisemitism with criticism of the Israeli government policy Labour antisemitism row: What Livingstone said On calling a Jewish journalist a “concentration camp guard” whilst Mayor of London I can’t tell if a journalist is Jewish or Catholic or anything. If a journalist is chasing you down the street at nine of clock at night you might be rude to them. Some people might have hit him! He said he was just doing his job. We went all the way to the High Court and the judge opened his judgement by saying ‘I hope no one here is going to suggest that Mr Livingstone is antisemitic’. We won the case Labour antisemitism row: What Livingstone said On claims about Hitler and Zionism I can’t tell if a journalist is Jewish or Catholic or anything. If a journalist is chasing you down the street at nine of clock at night you might be rude to them. Some people might have hit him! He said he was just doing his job. We went all the way to the High Court and the judge opened his judgement by saying ‘I hope no one here is going to suggest that Mr Livingstone is antisemitic’. We won the case Labour antisemitism row: What Livingstone said On John Mann I’d simply say to John Mann go back and check. Is what I say true, or is it not? The BBC, you’ve got a huge team of researchers, it will take just an hour or two to go back and confirm. I was asked a question, I answered it. I have never in 45 years since I won my first election, I have never lied. I have always answered the question Labour antisemitism row: What Livingstone said On raising the issue if Hitler It lays you open to people smearing and lying about you. I’ve always answered the questions put to me and that simple fact is we’ve had a handful of people saying antisemitic things in the Labour Party, they’ve been suspended, some of them are on their way to being expelled, some of them have been expelled already Labour antisemitism row: What Livingstone said On people calling for him to be suspended All my usual critics – but the simple fact is I agree with them; there is no place for antisemitism in the Labour party. For them to suggest I am antisemitic is a bit bizarre considering we worked with Jewish groups and put on exhibitions about the scale of the holocaust, we worked with Jewish groups to tackling the scale of antisemitism back in the 1970s. I’ve always opposed every form of racism whether it’s against black people or Jews. I’m going to stay in the Labour party and continue to fight against all forms of racism and discrimination as I have my entire life

The Campaign Against Antisemitism group also criticised his win on Saturday, when Mr Corbyn beat rival Owen Smith with 62 per cent of members’ votes.

"Though notable Labour members have struggled bravely to stem the tide, the Labour Party is no longer a safe place for British Jews," said Gideon Falter, Chairman of Campaign Against Antisemitism.

"We require the Party to adopt and firmly and transparently apply the international definition of anti-Semitism to the many outstanding cases amongst its members, including the disciplinary complaint that we have now instigated against Jeremy Corbyn.”

The action is over a video posted on Mr Corbyn's official Facebook and Twitter accounts where supporters answer questions on topics they are ”tired of hearing“ about, including anti-Semitism.

Speaking in June, Mr Corbyn called for a “civil discourse” and reasoned debate.

“Modern anti-Semitism may not always be about overt violence and persecution, though there is too much of that even to this day,” he said.