(CNN)A federal judge in California late Tuesday temporarily blocked the Trump administration's efforts to end the Deferred Action for Childhood Arrivals program.
But the ruling is limited -- the administration does not need to process applications for those who have never before received DACA protections, he said.
The Trump administration announced the move to draw down the program last September with a planned end for early March. DACA protected young undocumented immigrants who came to the US as children from deportation.
The fate of DACA and the roughly 700,000 "Dreamers" is the subject of heated negotiations in Washington, where President Donald Trump, Republicans and Democrats are searching for a way to allow Dreamers to stay while also addressing border security concerns. It is not clear how the order will impact those talks.
Alsup said "plaintiffs have shown that they are likely to succeed on the merits of their claim that the rescission was arbitrary and capricious" and must be set aside under the federal Administrative Procedures Act.
The judge said a nationwide injunction was "appropriate" because "our country has a strong interest in the uniform application of immigration law and policy."
"Plaintiffs have established injury that reaches beyond the geographical bounds of the Northern District of California. The problem affects every state and territory of the United States," he wrote.