Just two days before President Obama’s historic executive action for undocumented immigrants was set to begin its rollout, a Texas judge has put key portions of the executive order on hold. 

U.S. District Judge Andrew Hanen issued his ruling in Texas v. United States, a lawsuit backed by 26 states challenging President Obama’s executive action. Hanen ruled in a lengthy opinion that Obama didn’t follow proper procedural requirements before announcing his plan to offer short-term work permits and protection from deportation for an estimated five million undocumented immigrants, and has temporarily halted some provisions of the executive action. The White House has announced plans to immediately appeal the ruling, the Los Angeles Times reported.

The executive action was set to apply to undocumented immigrants who came to the U.S. as children and undocumented parents with U.S. citizen children who also cleared a host of other requirements. United States Citizenship and Immigration Services set a February 18 start date to begin accepting applications for the expanded class of undocumented immigrants who came to the U.S. as children. 

Hanen made clear that his ruling didn’t apply to Obama’s first executive action from 2012, which gave certain young undocumented immigrants who’d come to the U.S. as children similar protection from deportation and work permits.

Advocates, too, stressed that the ruling is only the beginning of a longer fight. “Despite its extreme and inflammatory rhetoric,” ACLU’s Immigrants’ Rights Project director Cecilia Wang said in a statement, “the Texas court decision does not explicitly hold that DAPA, DACA, or any other part of the federal government’s executive action is unconstitutional.”

Prior cases challenging Obama’s first executive action, including one brought by the union which represents Immigration and Customs Enforcement officers, have been dismissed. “We are confident that the Appeals Court will quickly determine that it has no legal merit, as did the only other court that considered a challenge to President Obama’s executive action,” the National Day Laborer Organizing Network’s Jessica Karp Bansal said in a statement.