Former London mayor Ken Livingstone was at it again this week, repeating his claim that the man responsible for the murder of six million Jews was in fact a Zionist and blaming “the Israel lobby” for his suspension.

Jewish representatives from the Board of Deputies called for his “immediate” expulsion from Labour, saying “every day he is not expelled is a stain on the party,” after he reappeared on radio to repeat his claims about Hitler.

In conversation with Vanessa Feltz, on whose show he first made the claims in April while defending offensive comments from Labour MP Naz Shah, Livingstone cited material at Israel’s Holocaust Museum to defend his views.

“If you go to Yad Vashem, one of the pamphlets they sell is one that talks about the deal done between Hitler and the Zionists in the 1930s,” he said. “If you are being given that at the Holocaust Memorial I think you might suspect it’s true.”

Livingstone said he had a “whole sheaf of documents and evidence” to show that Hitler had initially wanted to transfer Jews to Palestine, and rounded on “dour MPs” aiming to oust Jeremy Corbyn as party leader.

“The fact that during the 1930s Hitler collaborated with the Zionists and supported them because he believed that a solution to his problem – the Jews – was that they should all move to Palestine,” Livingstone told Feltz.

“Then in the 1940s that changed and he decided on genocide. And that’s the point I made on your programme. I’m just surprised that people didn’t check that it was true before they started screaming ‘Nazi apologist’.”

In a subsequent interview with the BBC, he reiterated that he had been referring to “the deal Hitler did with the Zionists in the 1930s,” adding: “If I had said Hitler was a Zionist, I wouldn’t just have apologised, I would have gone straight to my doctor. To suggest that Hitler was a Zionist is mad. He loathed and feared Jews all his life but he did do a deal with the Zionist movement in the 1930s.”

His latest comments, during which he blamed “a well-orchestrated campaign by the Israel lobby to smear anyone who criticises Israeli policy as anti-Semitic,” drew an angry response from Jewish leaders, who said Livingstone was “re-writing” history.

“Hitler’s persecution of the Jews started early in the 1930s,” said Board of Deputies’ vice-president Marie van der Zyl.

“He expressed his loathing for Zionism in the 1920s. But yet in 2016 Ken Livingstone seems to want to rewrite history to make it seem like Zionism was responsible for the Holocaust, which is as false as it is grotesquely offensive. Every day that Labour does not expel him is a stain on the party.”