All requests from refugees and illegal migrants from Africa to convert to Judaism have been rejected over the past year, according to a source in the Prime Minister's Office.

The source could not provide exact figures but said "many dozens" of such requests were rejected. Conversion falls under the auspices of the PMO.

"Dozens of Africans come straight to our offices in Tel Aviv, try to convince us to allow them to submit a request that would be examined by an exceptions committee," a PMO official said on the sidelines of the PMO conversion department's annual convention last week. "Of course, all the requests were rejected."

Rabbi Seth Farber, the founder and director of Itim, which advocates on behalf of those who need help navigating Israel's religious bureaucracy, said the main problem is the exceptions committee itself.

There is no reason to convert people if they are just exploiting the conversion process to become Israeli citizens, said Farber. But he noted that most of those appearing before the exceptions committee are the non-Jewish partners of Israelis, and most are not from Africa.

"They go to the state system for conversion, but the exceptions committee doesn't let them begin the process and drags it on for years," said Farber. "The reason is that the committee's criteria have become tougher, but primarily that it's just not functioning.

"It's easier for the conversion department to put out rumors about migrants who want to start the process, as though the main problem facing conversion in Israel is Africans," he said.

Last week's convention, which took place in Jerusalem and was attended by rabbis, rabbinic judges and conversion advocates, indicated that the rate of conversion is decreasing even as the proportion of Israelis with no declared religion is on the rise.

Though there were fewer immigrants from Ethiopia and the former Soviet Union who completed the conversion process last year, compared with 2010, the number of converts from other countries went up, from 673 to 710. Most are non-Jewish partners of Israelis who entered the country as either tourists or migrant laborers.