The beleaguered Employment Non-Discrimination Act (ENDA) hit an unexpected stumbling block Tuesday, when six national gay rights organizations led by the American Civil Liberties Union (ACLU) publicly withdrew their support for what was once hailed as landmark legislation to protect LGBT individuals in the workplace, citing objections to the bill’s religious exemptions.

In a statement signed by the Gay & Lesbian Advocates & Defenders, Lambda Legal, the National Center for Lesbian Rights, and Transgender Law Center, the ACLU announced that they are withdrawing support for ENDA. The National Gay and Lesbian Task Force filed a separate but similar statement. The organizations’ argument against legislation they once strongly supported stems from a provision in the bill that allows some employers to continue to discriminate based on sexual orientation and gender identity on religious grounds.

"Federal legislation to protect LGBT people from workplace discrimination is way beyond overdue, but Congress has no place giving religiously affiliated employers a license to discriminate against LGBT workers," said Laura W. Murphy, director of the ACLU’s Washington Legislative Office. "We can no longer support a bill that treats LGBT discrimination as different and somehow more legitimate than other forms of discrimination."

The Human Rights Campaign, who remains the only major LGBT rights organization supporting the bill, issued a short statement: "HRC supports ENDA because it will provide essential workplace protections to millions of LGBT people."

The move to withdraw support stems from the controversial U.S. Supreme Court decision in the Hobby Lobby case that allows closely held for-profit corporations to deny coverage for contraceptives as mandated by the Affordable Care Act (ACA), on the grounds of religious objections. The decision was an interpretation of the Religious Freedom Restoration Act, which prevents the government from enacting laws that substantially burden a person’s exercise of free religion.

From the joint statement issued by the ACLU, GLAD, NCLR, Transgender Law Center and Lambda Legal:

The provision in the current version of the Employment Non-Discrimination Act (ENDA) that allows religious organizations to discriminate based on sexual orientation and gender identity has long been a source of significant concern to us. Given the types of workplace discrimination we see increasingly against LGBT people, together with the calls for greater permission to discriminate on religious grounds that followed immediately upon the Supreme Court’s decision last week in Burwell v. Hobby Lobby, it has become clear that the inclusion of this provision is no longer tenable. It would prevent ENDA from providing protections that LGBT people desperately need and would make very bad law with potential further negative effects. Therefore, we are announcing our withdrawal of support for the current version of ENDA.

In a separate statement release by the National Gay and Lesbian Task Force, Executive Director Rea Carey said:

The morning after the Supreme Court’s Hobby Lobby ruling, we all woke up in a changed and intensified landscape of broad religious exemptions being used as an excuse to discriminate. We are deeply concerned that ENDA’s broad exemption will be used as a similar license to discriminate across the country. We are concerned that these types of legal loopholes could negatively impact other issues affecting LGBT people and their families including marriage, access to HIV/AIDS treatment and prevention and access to other reproductive health services. As one of the lead advocates on this bill for 20 years, we do not take this move lightly but we do take it unequivocally - we now oppose this version of ENDA because of its too-broad religious exemption. We cannot be complicit in writing such exemptions into federal law.

ENDA, which passed the Senate in 2013, has been stalled in the Republican-controlled House of Representatives, where House Speaker John Boehner (R-OH) has refused to put it forth for a vote.

In June, President Barack Obama announced that he will issue an executive order that would bar federal contractors from discriminating against LGBT employees. The statement release Tuesday by the ACLU opposed any inclusion of a religious exemption in the order.