Rumored wedding bells for Bar Refaeli and Leonardo DiCaprio may ring true or false, but these are already being muffled by controversy.

Supermodel Bar Refaeli is one of Israel's most successful "exports." But with fame comes responsibility -- and now an Israeli organization is beseeching Refaeli not to wed Leonardo DiCaprio -- out of a responsibility to future generations.

"It is not by chance that you were born Jewish," wrote Baruch Marzel in a letter he sent Refaeli through her mother (and that promptly appeared in the press). "Your grandmother and her grandmother did not dream that one of their descendants would one day remove the family's future generations from the Jewish people. Assimilation has forever been one of the enemies of the Jewish people."

Marzel, a well-known stalwart among Israel's ultra-nationalists, appealed to Refaeli on behalf of an organization named "Lehava." In Hebrew, this means "flame:; it is also the Hebrew acronym for "Preventing Assimilation in the Holy Land."

The organization, according to its Facebook page (in Hebrew) provides assistance to Jewish girls in relationships with non-Jews, especially Arabs. There are other organizations in Israel that specialize in extricating Jewish women from marriages and other relationships with Arabs. Last month, Yad L'achim held an event for 100 women "rescued from Arab villages."