In the biggest setback yet for the Trump administration in its attempt to end a program that shields some young adults from deportation, a federal judge ruled today that the protections must stay in place and that the government must resume accepting new applications.

Judge John D. Bates of U.S. District Court for the District of Columbia said that the administration’s decision to terminate the program, Deferred Action for Childhood Arrivals, or DACA, was based on the “virtually unexplained” grounds that the program was “unlawful.”

The judge stayed his decision for 90 days and gave the Department of Homeland Security the opportunity to better explain its reasoning for canceling the program. If the department fails to do so, it “must accept and process new as well as renewal DACA applications,” Bates wrote in his decision.

The ruling was the third in recent months against the Trump administration’s rollback of DACA. Federal judges in Brooklyn and in San Francisco each issued injunctions ordering that the program remain in place. Neither of those decisions, however, required the government to accept new applications.

Bates was nominated by President George W. Bush in 2001. He described the Trump administration’s decision to phase out DACA as “arbitrary and capricious because the department failed adequately to explain its conclusion that the program was unlawful.”

The Supreme Court in late February declined an unusual White House request that it immediately decide whether the Trump administration can shut down the program.

The Obama administration established the DACA program based on the premise that people brought to the United States as children should be treated as low priorities for deportation. About 700,000 unauthorized immigrants, the majority of them brought to the United States as children, had signed up. The program gives young immigrants, who are referred to as Dreamers after a proposal in Congress called the DREAM Act and must renew their DACA status every two years, the ability to work legally in the country.

The Trump administration officially rescinded DACA in March but the program has allowed the Dreamers to renew applications after previous court orders.

In a statement, the Department of Justice said that it “will continue to vigorously defend this position, and looks forward to vindicating its position in further litigation.”