(JTA) – The Orthodox Union joined an open letter signed by 26 other Jewish organizations opposing separation of migrants’ families at the border.

The decision to sign the letter on Friday came two days after the O.U., an umbrella Orthodox group, hosted Attorney General Jeff Sessions at its annual conference in Washington D.C., where he spoke to a friendly crowd about protecting religious liberty for houses of worship, and other matters. In May, Sessions’ department instituted a policy to separate migrant families after they cross the U.S. border illegally.

O.U. officials were assailed on social media and in a petition organized by the liberal rabbinic human rights group T’ruah for feting Sessions, and replied that they had brought up the immigration issue with him privately. On Thursday, June 14, one day after hosting Sessions the Orthodox Union released a statement criticizing the Trump separation policy.

Under the policy implemented in recent months, every illegal migrant who crosses the United States border is prosecuted and detained. Because children cannot be prosecuted with adults, they are reclassified as unaccompanied minors and taken away, either to mass children’s shelters or foster homes.

Critics of the policy say forcibly separating parents and children is traumatizing and draconian. Sessions says it’s a necessary measure to enforce border security.

“This policy undermines the values of our nation and jeopardizes the safety and well-being of thousands of people,” the Jewish open letter says. “As Jews, we understand the plight of being an immigrant fleeing violence and oppression. We believe that the United States is a nation of immigrants and how we treat the stranger reflects on the moral values and ideals of this nation.”

The letter signed by 26 national Jewish organizations, including the Anti-Defamation League, Jewish Council for Public Affairs and HIAS, urges the administration “to immediately rescind the ‘zero tolerance’ policy and uphold the values of family unity and justice on which our nation was built.”

Among the signers of the letter are the leading organizations of the Conservative, Reform and Reconstructionist movements. The addition of the O.U. means that top representative bodies of all four major American Jewish denominations have come out against the policy. It is rare that the O.U., which generally takes conservative political positions, agrees with the other three movements on a matter of domestic government policy.

Religious groups across the spectrum, Jewish and not, have opposed the policy, and the O.U. is among the most recent conservative religious organizations to oppose it. It has been criticized in recent days by the Southern Baptist Convention, the U.S. Conference of Catholic Bishops and the Rev. Franklin Graham, the late Billy Graham’s son.

CAP: Officers taking a group of Central American asylum seekers into custody near McAllen, Texas, June 12, 2018. (John Moore/Getty Images)