The Supreme Court blocked the Trump administration from ending the Deferred Action for Childhood Arrivals (DACA) program on Thursday.

In a 5-4 decision, the justices said the Trump administration did not sufficiently justify their decision, as required by federal law, to end the program which protects nearly 700,000 undocumented immigrants from deportation. The ruling does not prevent DACA from being terminated in the future.

“The dispute before the Court is not whether [Department of Homeland Security] may rescind DACA. All parties agree that it may. The dispute is instead primarily about the procedure the agency followed in doing so,” Chief Justice John Roberts wrote in the majority opinion.

Roberts, a conservative has become an important swing vote on the issues of immigration policy.

He upheld President Donald Trump‘s Muslim-majority country immigration ban, but joined the liberal justices in blocking the administration from adding a citizenship question to the 2020 census.

Roberts’ majority opinion was joined by Justices Ruth Bader Ginsburg, Stephen Breyer and Elena Kagan. Justice Sonia Sotomayor also signed onto the majority opinion, but noted that DACA may be unable to be rescinded on equal protection grounds.

Conservative Justices Clarence Thomas, Samuel Alito, Neil Gorsuch and Brett Kavanaugh dissented.

“The Court could have made clear that the solution respondents seek must come from the Legislative Branch. Instead, the majority has decided to prolong DHS’ initial overreach by providing a stopgap measure of its own,” Thomas wrote in his dissenting opinion. “In doing so, it has given the green light for future political battles to be fought in this Court rather than where they rightfully belong — the political branches.”

Trump criticized the ruling as politically motivated and pledged to appoint more conservative judges in the future.

“These horrible & politically charged decisions coming out of the Supreme Court are shotgun blasts into the face of people that are proud to call themselves Republicans or Conservatives. We need more Justices or we will lose our 2nd. Amendment & everything else. Vote Trump 2020!” Trump tweeted.

“I will be releasing a new list of Conservative Supreme Court Justice nominees, which may include some, or many of those already on the list, by September 1, 2020,” Trump added. “If given the opportunity, I will only choose from this list, as in the past a Conservative Supreme Court Justice… Based on decisions being rendered now, this list is more important than ever before (Second Amendment, Right to Life, Religous Liberty, etc.) – VOTE 2020!”

Trump’s campaign largely centered on ending illegal immigration, including by ending former President Barack Obama’s “illegal executive amnesties.”

Obama created DACA via executive order in 2012, which now boasts an enrollment of nearly 700,000. Undocumented DACA immigrants, sometimes known as “Dreamers,” are eligible for work permits, driver’s licenses and health insurance.

Since SCOTUS upheld the administration’s ability to end the program, the fate of the program will likely be determined in the 2020 general election.