A federal judge on Thursday struck down a Biden administration policy aimed at making it easier for some undocumented immigrants married to U.S. citizens to gain access to citizenship.

The program, hailed as one of the largest presidential actions to help immigrant families in years, helped undocumented spouses and stepchildren of U.S. citizens to apply for a green card without having to leave the country first.

The temporary relief from deportation brought brief feeling of security to some 500,000 immigrants expected to benefit from the program before Texas-based U.S. District Judge J. Campbell Barker. put it on hold in August, a few days after the candidates filed their documents.

Barker ruled Thursday that the Biden administration overstepped its authority in implementing the program and stretched the legal interpretation of relevant immigration law “past its breaking point.”

The Biden administration’s short-lived initiative, known as “Keeping Families Together,” likely could not have remained in place after Donald Trump took office in January. But its early termination creates greater uncertainty for immigrant families as many prepare for Trump’s return to the White House.

Trump’s election victory this week sets the stage for a rapid crackdown on undocumented people after the Republican ran on a promise to “mass deportation”. The president-elect energized his supporters on the campaign trail with a litany of anti-immigrant statements, including that immigrants were “poisoning the blood” of the nation.

During his first term, Trump appointed Barker as a judge in Tyler, Texas, who sits on the 5th U.S. Court of Appeals, a favored venue for advocates of conservative arguments.

Barker had suspended the immigration initiative after Texas and 15 other states, led by their Republican attorneys general, filed suit. legal challenge accusing the executive branch of bypassing Congress to help immigrant families for “blatant political purposes.”

Republicans argued the initiative created costs for their states and could attract more migrants to the United States.

The policy would have applied to people who have lived continuously in the United States for at least 10 years, do not pose a security threat, and would have used existing legal authority known as “parole in place” which provides protections against eviction.

People married to a citizen before June 17, the day before the program was announced, could pay a $580 application fee and fill out a lengthy application explaining why they deserve humanitarian parole. If approved, applicants will have three years to apply for permanent residence and obtain a work permit.

It was unclear Thursday whether anyone had received approval under the program, which only accepted applications for about a week before the federal judge suspended it.

Non-citizen spouses are already eligible for legal status but often must apply for it from their home country. The process typically includes waiting for several years outside the United States, which can separate family members with different immigration statuses.