The US Supreme Court on Monday allowed the Trump administration to proceed with a rule that aims to deny permanent residency and citizenship to immigrants who claim welfare benefits.
The top chamber's five conservative justices outvoted their four progressive colleagues to support a request by President Donald Trump to lift a New York court injunction that had blocked the rule's application.
Trump has made clamping down on immigrants a cornerstone of his presidency, and Monday's ruling is the latest by the Supreme Court in favor of his migrant-related policies.
"Today the Court (rightly) grants a stay, allowing the government to pursue (for now) its policy everywhere save Illinois," the Supreme Court ruling said.
The White House lauded the ruling, calling it a "massive win for American taxpayers, American workers, and the American Constitution" in a statement.
Announcing last August a new definition of the longstanding "public charge" law, Trump said that "to protect benefits for American citizens, immigrants must be financially self-sufficient."
The new rules threatened to set back the citizenship hopes of millions of mostly Hispanic migrants who work for low wages and depend in part on public services to get by.
Under the changes, the 22 million non-citizen residents of the United States using food stamps, public healthcare and other welfare will not be able to obtain green cards or US citizenship, according to the White House.
Additionally, hopeful migrants will not be granted resident visas if they are deemed too poor and likely to need public assistance.
Immigration officials will have more leeway to deny the entry of immigrants or to grant a certain migrant status to those receiving public assistance.
A coalition of states in August quickly sued Trump's administration over the rule. They said it was unconstitutional and disproportionately targeted non-white immigrants.
Ken Cuccinelli, acting Director of US Citizenship and Immigration Services, welcomed Monday's ruling.
He said the Supreme Court "is fed up" with injunctions by judges whom he said are trying to impose policy rather than enforce the law.
"I hope some of these activist district court judges finally get the message that they need to deal with the law, not their policy preferences. If they want to do that, get out and run for Congress," he said.
The Democratic National Committee, charged with the process of choosing the party's challenger to Trump in this year's elections, countered that "it's sickening to see the United States Supreme Court rubber-stamp Trump's extreme, anti-immigrant, xenophobic agenda."
In September, the Supreme Court said Trump could enact severe restrictions on asylum seekers.
That followed a July ruling backing the president's move to divert billions of dollars in Pentagon funds for extending or rebuilding stretches of wall on the Mexican border.