The 90-second ad shows Mayall mimicking Hitler's sieg heil salute and shouting: "Ein Volk! Ein Reich! Ein Euro! (One people, one Reich, one euro)".
A spokesman for the Board of British Jews called the use of Hitler in the ads "tasteless and highly inappropriate". It added: "It is bound to cause offence to all those who experienced at first hand the evils of the Third Reich."
The German embassy yesterday said it was ludicrous to associate Hitler with the euro.
Britain in Europe, the pro-euro group, said that anti-Europeans appeared to have given up on serious argument and replaced it with a series of indignant responses instead.
On behalf of Britain in Europe, Lord Brittan said: "This tasteless ad shows the underlying nastiness behind much of the 'no' campaign, as well as an element of desperation."
Kate Hoey, the former sports minister, defended the campaign.
She said: "Anyone who doesn't laugh, I think should get a life. This is going to reach people who, quite frankly, politicians aren't getting through to."
Yesterday, Bob Geldof became the latest star to add his weight to the campaign, which breaks across the country next week.
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