Sean Spicer, the White House press secretary, has spent the last two days issuing a series of apologies for comments he made comparing Syria’s president Bashar al-Assad to Hitler, claiming initially that “even Hitler didn't sink to using chemical weapons”.

When an appalled Washington press corps asked Mr Spicer to clarify his remarks, made at a Tuesday press conference at the White House, he made things worse. He said: “I think when you come to sarin gas, [Hitler] was not using the gas on his own people the same way that Assad is doing…He brought them into, um, the Holocaust centres  —  I understand that. But I’m saying in the way Assad used them where he went into towns, dropped them down into the middle of towns, it was brought  —  the use of it  —  and I appreciate the clarification.”

There was an immediate outcry at Mr Spicer’s comments, the strongest reaction coming from the chief executive of the Anne Frank Centre for Mutual Respect Steven Goldstein, who issued an outraged statement calling for the press secretary to be fired.

Commenting on Mr Spicer's remarks, Karen Pollock MBE, Chief Executive of the Holocaust Educational Trust said: “Our challenge is not only to fight ignorance through education, but to defend the truth of the Holocaust. Lazy, ignorant or deliberately misguided references to Hitler and the Holocaust should be called out for what they are.”

His comments and subsequent apologies were made worse by the fact that they took place over the opening days of Passover.

Mr Goldstein said Mr Spicer’s apologies - which included a direct phone call to the Jewish tycoon Sheldon Adelson, a long-standing supporter of President Trump - were “too little, too late”.

Mr Goldstein, a fierce critic of the Trump administration, was dismissive of the Spicer apology. He described it as not “from the heart” but rather “a bureaucratic response to an outcry”.

In Israel, the Likud minister Yisrael Katz, who holds the intelligence and transport portfolios, originally demanded that Mr Spicer apologised or resigned. But later, when it became clear that Prime Minister Benjamin Netanyahu was not going to add to the furore, Mr Katz backed down and appeared to accept the Spicer apologies.