Nearly one hundred members of Congress, including five presidential candidates, have added their names to a pair of letters calling on Secretary of State Mike Pompeo to immediately reverse a State Department policy that withholds American citizenship from some children of U.S. citizens who are born abroad.

One letter, led by Sens. Jeff Merkley of Oregon and Kamala Harris of California and signed by 17 other Democratic members of the chamber, calls the policy “a thinly veiled attack on LGBTQ Americans whose children are conceived through the use of egg donors and gestational surrogacy.”

“Your Department’s reinterpretation of immigration law to deny the constitutional right of citizenship to the children of same-sex couples who are born outside the United States is extraordinary and deeply disturbing,” the letter states. The letter’s 19 signatories urge Pompeo to immediately drop the State Department’s appeal of a court ruling striking down the policy, “and make it clear that every U.S. married couple is entitled to the same rights under the U.S. Constitution, no matter whom they love.”

In addition to Merkley and Harris, the letter was signed by Sens. Ed Markey (D-MA), Chris Murphy (D-CT), Patrick Leahy (D-VT), Bernie Sanders (I-VT), Catherine Cortez Masto (D-NV), Tom Udall (D-NM), Dianne Feinstein (D-CA), Jacky Rosen (D-NV), Dick Durbin (D-IL), Amy Klobuchar (D-MN), Tammy Duckworth (D-IL), Chris Coons (D-DE), Cory Booker (D-NJ), Maggie Hassan (D-NH), Bob Casey (D-PA), Tim Kaine (D-VA), and Ron Wyden (D-OR).

Another letter, signed by the co-chairs of the Congressional LGBT Equality Caucus and every gay, lesbian and bisexual member of the House of Representatives, was delivered to Pompeo on Thursday afternoon. In that letter, the 80 signatories called the policy “discriminatory and cruel.”

“Welcoming a new child into a family should be a time of joy and excitement, but instead it is being met by your Department treating these couples differently than their different-sex counterparts,” the second letter, led by Reps. Deb Haaland (D-N.M.), David Cicilline (D-R.I.) and Tom Malinowski (D-N.J.), stated.

The policy in question changes the State Department’s interpretation of the Immigration and Nationality Act (INA), a 1952 law that codifies eligibility for U.S. birthright citizenship. Under the policy, children born abroad via assisted reproductive technology like gestational surrogacy or sperm donation are considered to have been born “out of wedlock,” even if their parents are legally married U.S. citizens.

“Out of wedlock” births abroad face a bevy of legal and logistical hurdles to gaining birthright American citizenship, and the policy has led to numerous instances of the children of U.S. citizens being effectively turned away at the border.

“They basically take our marriage, and they say ‘It doesn’t mean anything. Your child was born out of wedlock,’” Adiel Kiviti, whose three-month-old daughter was born with the help of an egg donor and a gestational surrogate in Canada, told The Daily Beast last month. “We were there when she was born, she took her first breaths in our arms. Make no mistake: We are her parents—we are her only parents on her only birth certificate.”

“This is a very clear attack on families, on American families,” his husband Roee, who married Adiel in California in 2013, said at the time. “Denying American married couples their rights to pass their citizenship, that is flat-out discrimination, and everyone should be concerned about this.”

Two same-sex couples have sued the State Department over the policy, which they say disproportionately affects LGBT families, who stick out when seeking government documents that recognize the birthright citizenship of children born abroad.

The INA makes no reference to biology in determining birthright citizenship of children born abroad to married U.S. citizens, giving the policy little textual support in law. In February, a federal judge ruled that “the basis for the State Department’s imposition of a biological requirement is its strained interpretation” of existing immigration law, and dismissed attempts to institute a biological testing standard for the children of binational married couples as “unilateral.”

But the State Department has appealed that ruling, and has fought to summarily dismiss a suit brought by another same-sex couple against the policy.

The publication of a story by The Daily Beast on the policy brought renewed national attention to the issue, prompting nearly every Democratic presidential candidate, as well as senior congressional leadership, to call for the policy’s reversal.

“Once again, the Trump administration is demonstrating just how far they are willing to go to undermine our core values and advance their hateful agenda,” said House Speaker Nancy Pelosi in a statement last month. “The State Department must uphold our laws, end this cruel and inhumane policy and treat every family with the dignity and respect that they deserve.”

In the letter from Senate Democrats, signatories called the department’s legal defense of the policy part of a larger tapestry of decisions that have hurt LGBT Americans, from its decision to not grant visas to the same-sex partners of some foreign diplomats to what they called the “muted” response to anti-LGBT persecution abroad.

“Every new American parent should focus on celebrating the birth of a child, not be consumed with fear that all members of their family may not be welcomed back home to the United States,” the signatories wrote. “The United States can best advocate for LGBTQ rights around the world by living its values at home, especially during this month of Pride.”

The State Department did not immediately respond to a request for comment on the letter.