Washington CNN  — 

The Supreme Court held on Monday that the government can block non-citizens who are in the US under a program that temporarily protects them from deportation in certain situations from applying for a green card if they entered the country unlawfully.

Justice Elena Kagan wrote for a unanimous court.

“Today’s decision is not just a setback for those immigrants currently in Temporary Protected Status who did not enter the United States lawfully; it also reinforces the barriers that Dreamers would face until and unless Congress provides a statutory path to some kind of permanent lawful status,” said Steve Vladeck, CNN Supreme Court analyst and professor at the University of Texas School of Law.

“The Executive Branch may have some authority to confer forms of temporary legal status on those who crossed the border without permission, but the Supreme Court today reinforced, however indirectly, that only Congress can provide a permanent answer,” he added.

The case concerns Jose Sanchez and Sonia Gonzales, a New Jersey couple who came to the US illegally in 1997 and 1998 and now have four children. Their youngest was born in the US and is a citizen.

Following a series of earthquakes in El Salvador in 2001, they applied for and received Temporary Protected Status, which shields foreign nationals present in the US from removal if they have been subject to armed conflicts or environmental disasters in their homeland. In 2014, the couple sought to apply to “adjust” their status to become lawful permanent residents and apply for a green card.

The US Citizenship and Immigration Services denied their application, noting that they were ineligible to apply because they had not entered the country legally and never been formally admitted to the US.

The case confronted two sections of immigration law: one that says that those in TPS should be considered as “maintaining lawful status,” and another that says in order to adjust status, an individual in TPS must have been admitted lawfully.

Kagan said that the conferral of TPS status does not make an unlawful entrant like Sanchez eligible for a green card.

Kagan said that there was “no dispute” that Sanchez entered the US “unlawfully, without inspection.” She said that a “straightforward” application of immigration law supports the government’s decision to deny him status as a lawful permanent resident because he was not lawfully admitted.

“He therefore cannot become a permanent resident of this country,” Kagan concluded.

Currently, there are about 400,000 people with TPS status in the country and 85,000 have managed to adjust status.

Although a district court ruled in favor of the couple, an appeals court reversed. It held that TPS does not “constitute an admission.”

In court, Amy M. Saharia, a lawyer for Jose and Sonia Gonzales, argued that having been admitted is “inherent” in the TPS status. But Michael R. Huston, assistant to the US solicitor general, drew a line between status and admission, arguing against the couple.

The government said that while Congress had made some individuals eligible to adjust their status if they met certain criteria and had a sponsor, it was not available to those who had not made a lawful entry. Huston said the government had “reasonably determined” that Congress did not “establish TPS as a special pathway to permanent residents for non-citizens who are already barred from that privilege because of pre-TPS conduct.”

He urged the court to defer to the position taken by the agency in the case and he noted that there are “tens of thousands” of TPS holders who have adjusted their status, but they had been lawfully admitted as a student or an au pair or a temporary worker. He said that TPS holders know that it is a temporary form of relief from removal and that it “will not last forever.” At an early point in the case, the Trump administration had argued that those in the TPS program could never try to get green cards. The Biden administration’s position leaves open the opportunity for the government to change its mind.

This story has been updated with additional details.

CNN’s Devan Cole contributed to this report.