Rabbi Julie Schonfeld, who leads the Rabbinical Assembly, said the Conservative movement was “shocked and extremely outraged” at the decision, which she called “unlawful.”

“This is completely inconsistent with more than two decades of Israeli practice of Conservative converts — who are by the way halakhically converted to Judaism under our auspices — who had been recognized as Jewish for the purposes of the Law of Return,” she told JTA on Friday, using a phrase meaning that something was done in accordance with Jewish law, or halakhah.

The Law of Return gives anyone who has a Jewish grandparent, is married to a Jew or has converted to Judaism the right to move to Israel.

On Thursday Haaretz reported that Israel’s Interior Ministry had ruled not to recognize the conversions of Ugandan Jews for the purposes of immigrating to the country. The government made the ruling in the case of Kibita Yosef, a Ugandan Jew seeking to immigrate to Israel, but reportedly stated that the decision represented Israel’s stance on the Ugandan Jewish community, not just Yosef.

The ministry said Yosef, who is staying at a kibbutz in southern Israel, had to leave the country by June 14, and that he could challenge its decision in the High Court of Justice, according to the report.

Schonfeld said that the Conservative movement and its allies were planning “to use all means at our disposal to see that this is reversed.”

The Uganda community, also called the Abayudaya, numbers approximately 2,000 and traces its roots to the early 20th century, when a former leader read the Bible and embraced Judaism. Most members were converted under the auspices of U.S. Conservative rabbis and thus are not recognized as Jewish by Israel’s mostly haredi Orthodox Chief Rabbinate.

In 2016, the Jewish Agency for Israel recognized the community forthe purposes of the Law of Return, seemingly opening a path for its members to immigrate to Israel. However, the Abuyudaya have struggled to obtain recognition to do so. In December, Israel denied a visa application by a member of the community to study at a yeshiva in Israel, leading to accusations of racism.

Schonfeld said the decision threatened not only converts affiliated with the Conservative movement.

“By specifically and explicitly undermining the authority of the Jewish Agency on this matter they are throwing into question converts across the board, including not only Conservative and Reform but also Orthodox conversions,” she said.

Non-Orthodox groups were already bracing for a fight over conversions before the Uganda story broke. This week, the Chief Rabbinate published a list further tightening its criteria for accepting Jews converted abroad. The non-Orthodox denominations and some Modern Orthodox groups have long resented the haredi Orthodox Chief Rabbinate’s controls over Jewish marriage, divorce, conversion and burial in Israel. However, it does not have authority over who can immigrate to the country.