(JNS) The leaders of seven major Jewish and Zionist organizations warned Israeli Prime Minister Benjamin Netanyahu that proposed changes to Israeli law could affect the unity of world Jewry.

“Any change in the delicate and sensitive status quo on issues such as the Law of Return or conversion could threaten to unravel the ties between us and keep us away from each other,” the leaders stated in a letter addressed to the prime minister.

The signatories included Mark Wilf, chairman of The Jewish Agency Board of Governors; Doron Almog, chairman of The Jewish Agency; Yaakov Hagoel, chairman of the World Zionist Organization; Steven Lowy, chairman of the World Board of Trustees at Keren Hayesod; Eric Fingerhut, president and CEO of Jewish Federations of North America (JFNA); and Julie Platt, chairwoman of JFNA.

They were referring to coalition deals signed between Netanyahu’s Likud Party and the Religious Zionist and Haredi parties calling for a change to the “grandparent clause” in the Law of Return. (Currently, an individual with a single Jewish grandparent is automatically eligible for Israeli citizenship.)

The issue came to the fore after a wave of immigrants from Russia and Ukraine entered Israel following Russia’s invasion of Ukraine, most of whom were not Jewish—only three in 10, according to mid-November data from Israel’s Population and Immigration Authority.

According to halacha, a person is Jewish if they or their mother is Jewish, or if they convert to Judaism.

There are currently 400,000 people in Israel who are not considered Jewish according to halacha.