Former Labour peer Alan Sugar has deleted a mocked-up tweet showing Jeremy Corbyn sitting in a car beside Adolf Hitler, after prompting calls from senior figures to “disown” it.

Lord Sugar, who was born into a Jewish family, posted a picture on social media with the Labour leader’s head superimposed onto someone’s body, with the caption: “When you’re pictured at Nuremberg and claim you thought you were going to a car rally”.

The move drew criticism from shadow chancellor John McDonnell, who has tried to quell the growing crisis over anti-Jewish sentiment in Labour, which spiralled after Mr Corbyn had to apologise for apparently defending an antisemitic mural in 2012.

It comes as a new poll found nearly three-quarters of Labour members believe the party’s problem with antisemitism is being exaggerated to damage the Labour leader.

Lord Sugar posted the now-deleted picture to his 5.5 million followers on Friday, with the comment: “Many a truer word spoken in jest”.

Mr McDonnell intervened, saying: “People have contacted me about Alan Sugar’s tweet. I just make this appeal to him. Please delete and disown it.

“We all desperately need to bring people together now. We can hold strong views about each other’s politics but now is the time to learn from each other and unite people.”

Other Labour MPs also complained, including Corbyn ally Chris Williamson, who said the post “promotes hatred and that is irresponsible”.

“I hope you will therefore swallow your pride, delete it and make a fulsome apology,” he added.

John Mann, chair of the All-Party Parliamentary Group against Antisemitism, said: “The use of Hitler/Nazi comparators is demeaning, unwarranted and dangerous. You damage the fight against antisemitism with this, Lord Sugar. Withdraw this and apologise please.”

Lord Sugar said the post was “a joke” and the “angry brigade like to moan”, before telling Mr McDonnell: “You need to get Corbyn to make a firm statement about antisemitism. There is no smoke without fire in Labour.”

Mr Corbyn sought to heal divisions with a Passover message on Friday, where he said he was an “ally” in the fight against abuse.

However his efforts to calm the situation were nearly derailed by Christine Shawcroft, the party’s former discipline chief who resigned over antisemitism, when she claimed the row was being “stirred up” to attack the Labour leader.

A YouGov survey for The Times found that only 19 per cent of Labour members think antisemitism is a serious issue in the party, while 77 per cent believe it is used to undermine the leader or stifle criticism of Israel.

Ms Shawcroft, a senior Momentum figure, stood down as chair of Labour’s disputes panel on Wednesday after it emerged she had questioned the suspension of a council candidate accused of Holocaust denial.

Around 40 Labour MPs and peers have demanded she be suspended from the party’s ruling body, the National Executive Committee (NEC).

Labour deputy leader Tom Watson has joined calls for her to step down, saying he hoped Christine Shawcroft would “explore her own conscience” and voluntarily give up her position.

He also said he believed it was “highly likely” that former London mayor Ken Livingstone – who remains suspended over comments suggesting Hitler supported Zionism in the 1930s – would be permanently expelled from the party.

In a public Facebook post, Ms Shawcroft said she was “not a Holocaust denier and I would not support a Holocaust denier”, adding: “This whole row is being stirred up to attack Jeremy, as we all know.”

In a later post, Ms Shawcroft said she was “deeply sorry” for the way she had handled the complaint about the local council candidate and knew “how much hurt it has caused”.

Ms Shawcroft said she had already announced she would not seek re-election to the NEC so will be leaving in the summer.

Mr Corbyn faced protests outside parliament this week, as well as criticism from senior Jewish figures, that he had failed to adequately address antisemitism in the Labour movement.

In his Passover message, Mr Corbyn said: “We in the Labour movement will never be complacent about antisemitism. We all need to do better.

“I am committed to ensuring the Labour Party is a welcoming and secure place for Jewish people.

“And I hope this Passover will mark a move to stronger and closer relations between us and everyone in the Jewish community.

“In the fight against antisemitism, I am your ally and I always will be.”