UPDATE 9 October 2019: Lord Dubs has now retracted his comments and apologised to Mr Rees-Mogg.

Lord Dubs told The Independent: "It is a universal principle that there must be clear evidence of antisemitism before such an accusation can be made. I apologised to Mr Rees-Mogg as this was clearly not the case in these circumstances."

He added: "George Soros has had a lot of antisemitic attacks over the years and we have to be careful about the language used to describe him."

Boris Johnson is facing calls to sack Jacob Rees-Mogg after the Commons leader was accused of making comments “straight from the far right’s antisemitic playbook” during a parliamentary debate.

Mr Rees-Mogg has become embroiled in a row over “dog whistle” comments he made about Hungarian businessman George Soros, who he described as the “Remoaner funder-in-chief”.

Mr Soros, a Jewish billionaire, has donated money to the Best for Britain campaign – but critics said the decision to single him out was a perpetuation of a common antisemitic trope.

Labour peer Alf Dubs, who escaped the Nazis on the Kindertransport, described the comments as “straight from the far-right’s antisemitic playbook”.

The row centres on an exchange between Mr Rees-Mogg and his Labour counterpart Valerie Vaz, who said hedge fund manager Crispin Odey – a backer of a no-deal Brexit – had “made £220m overnight as sterling slumped after the 2016 referendum result”.

In response, Mr Rees-Mogg said: “I remind her that one of the major funders, allegedly, of the Remain campaign, the Remoaner funder-in-chief, was one George Soros, who made £1bn when sterling crashed out of the exchange rate mechanism, which is five times as much as Mr Odey is said to have made.

“So I fear all she is saying is that Mr Soros is a better hedge fund manager than my good friend Crispin Odey, who is a great friend of mine and, indeed, supporter of mine.”

Lord Dubs, a Labour peer, said: “Boris Johnson must condemn his remarks about a Holocaust survivor and remove him from his cabinet.

“Like George Soros, I fled Nazi persecution, and like me, George Soros campaigns for European countries to give sanctuary to refugees today, just as I was given refuge as a child in 1939. Boris Johnson and his government don’t want vulnerable people who they see as being different to them coming to our country.

“Those are the same arguments that were used against me and other Jewish people coming here 80 years ago.”

Independent Minds Events: get involved in the news agenda

Labour MP David Lammy posted on Twitter: “George Soros ‘funder in chief’ ‘wink’ ‘wink’ ‘nudge’ ‘nudge’.

“Jacob Rees-Mogg don’t think we can’t hear you feeding antisemitic conspiracy theorists with this thinly veiled dog whistle.”

Mr Rees-Mogg and the Conservatives have been approached for comment.

Last year, Mr Soros donated £400,000 to the anti-Brexit campaign Best for Britain through his Open Society Foundations.