A new bill to change the rules governing how people who convert to Judaism are treated in Israel is threatening a domestic political crisis and has sparked a wider international debate on the nature of modern Judaism.
On Sunday Prime Minister Benjamin Netanyahu told his cabinet colleagues he would oppose the new law in the country's parliament, the Knesset. He warned it would alienate Jews living outside Israel, particularly those in the United States. The issue threatens to split his government.
The law again raises the issue of who is a Jew. It would give orthodox rabbis in Israel almost exclusive control over Jewish conversions, allowing them to determine who is recognized as Jewish and who can get married or buried in Israel as a Jew.
The scope of the bill has caused a furor among more liberal Jews from the Reform and Conservative movements that represent the majority of Jews living outside Israel.
People who are recognized as Jews under Reform and Conservative rules are now accepted in Israel and can become citizens. If this bill passes their identity as Jews may be questioned.
Rabbi David Saperstein from the Religious Action Center in Washington DC is in Israel campaigning against the law.
"It would be an enormous blow to the unity of the Jewish people and the principle of religious freedom in Israel, " he told the Associated Press. "The message will be sent out that the government of Israel does not accept our rabbis and our movement as legitimate."
The law was proposed by David Rotem a member of the secular and right wing Israel Is Our Home Party, which is led by Foreign Minister Avigdor Lieberman.
Most of the party's supporters come from the former Soviet Union and immigrated to the Jewish state in the 1992. However, hundreds of thousands of them have questionable ties to Judaism. The new law will make it easier for them to convert by establishing a new system of municipal rabbis. But liberal and conservative Jews are worried by the fact that the guidelines applied during the process of conversion will be determined by the country's orthodox Chief Rabbinate, giving it near-monopolistic power over the coversion issue.
Netanyahu is renowned for his links to the large Jewish community in the United States and he often courts its support in periods of sensitive diplomatic negotiations with the Obama administration. His opposition to the new law is thought to be inspired by his desire to prevent American Jews from feeling alienated from Israel.
Saperstein's Religious Action Center has launched a unprecedented campaign, calling on liberal and conservative Jews in the U.S. to send a letter or fax to Netanyahu. The center even offers suggested wording: "Such legislation would be an open attack on the legitimacy of non-Orthodox Jewry, which as you know comprises the vast majority of world Jerwry," the letter says. It goes on to call on Netanyahu "to intervene and urge immediate withdrawal of the bill."
But Netanyahu's ability to stop the bill may be limited. His two main coalition partners in the government, the religious Shas Party and Lieberman's Israel Is Our Home Party both support the bill.