Joan Rivers
The Jewish comedian provoked controversy when she compared supermodel Heidi Klum to a Nazi during an appearance on E!'s 'Fashion Police.

Jewish comedian Joan Rivers has courted controversy again by comparing supermodel Heidi Klum to a Nazi.

The 79-year-old star was blasted by a Jewish pressure group, the Anti-Defamation League (ADL), which said her comments on E! Entertainment's Fashion Police were "vulgar and hideous".

Commenting on the low-cut gold dress worn by the German-born star to Elton John's Aids Foundation Academy Awards viewing party Rivers said: "The last time a German looked this hot was when they were pushing Jews into the ovens."

Rivers doubled over in laughter but the ADL was not amused.

"Of all people, Joan Rivers should know better," national director and Holocaust survivor Abraham Foxman said.

"This remark is so vulgar and offensive to Jews and Holocaust survivors, and indeed to all Americans, that we cannot believe it made it to the airwaves.

"Making it worse, not one of her co-hosts made any effort to respond or to condemn this hideous statement, leaving it hanging out there and giving it added legitimacy through their silence.

"It is vulgar and offensive for anybody to use the death of six million Jews and millions of others in the Holocaust to make a joke, but this is especially true for someone who is Jewish and who proudly and publicly wears her Jewishness on her sleeve.'

The segment was first aired February 25, and has since been aired at least four times.

Rivers, who has refused to apologise, defended her statement and insisted that comedy helped to maintain public awareness of the Holocaust.

"My husband lost the majority of his family at Auschwitz, and I can assure you that I have always made it a point to remind people of the Holocaust through humour," she said.

Rivers has been accused of trivialising the Holocaust before.

In 2012, while criticising supermarket chain Costco's decision not to stock her book I Hate Everything...Starting With Me, she compared the retailer's policies to the Nazi regime.

Rivers responded to the backlash: "Don't talk to me about the Holocaust."