The Human Rights Campaign (HRC) and Lambda Legal on Friday said that they would challenge a Department of Health and Human Services (HHS) rule change that eliminates transgender protections in the Affordable Care Act, also known as Obamacare.

HHS released the final rule on Friday.

(Related: Biden criticizes Trump's rollback of transgender protections in health care.)

HHS's rule reverses an Obama-era regulation that expanded the definition of sex as it relates to discrimination in health care to include gender identity. HHS's new rule defines sex as “determined by biology.”

In separate statements, Lambda Legal and HRC said they would challenge the rule in court. It was not clear whether the groups planned to file separate lawsuits.

“We cannot and will not allow Donald Trump to continue attacking us. Today, the Human Rights Campaign is announcing plans to sue the Trump administration for exceeding their legal authority and attempting to remove basic health care protections from vulnerable communities including LGBTQ people. And, to add insult to injury, the administration finalized this rule on the anniversary of the Pulse shooting, where a gunman killed 49 people in an LGBTQ nightclub,” HRC President Alphonso David said in a statement.

“LGBTQ people get sick. LGBTQ people need health care. LGBTQ people should not live in fear that they cannot get the care they need simply because of who they are. It is clear that this administration does not believe that LGBTQ people, or other marginalized communities, deserve equality under the law. But we have a reality check for them: we will not let this attack on our basic right to be free from discrimination in health care go unchallenged. We will see them in court, and continue to challenge all of our elected officials to rise up against this blatant attempt to erode critical protections people need and sanction discrimination,” David said.

Lambda Legal also criticized the new policy and announced it would take legal action.

“Today's rule is a tragically failed public health policy and just flat out illegal,” said Omar Gonzalez Pagan, senior attorney at Lambda Legal. “We will be challenging the rule because at a time when the entire world is battling a dangerous pandemic, which in the United States has infected more than 2,000,000 people and killed more than 116,000, it is critical for everyone to have ready access to the potentially life-saving health care they need.”

In a lawsuit filed in March, Lambda Legal claimed that the Trump administration had failed to enforce LGBT nondiscrimination protections in HHS-funded programs.