The de Blasio administration is suing to block the White House from imposing a rule change that makes it easier to deny green cards and visas to immigrants seeking government financial assistance.

City lawyers filed papers in Manhattan federal court Monday seeking a preliminary injunction to block changes to the public charge rule from taking effect on Oct. 15. They argued that it would deter “millions of non-citizens and their family members from accessing public benefits they are lawfully entitled to receive, causing tremendous economic, public health, and other harms.”

The current rule makes it possible to brand immigrants who accept public assistance as a “public charge” — meaning they would likely rely on public assistance in the future. The federal government can use public charge status when weighing whether to grant green cards and visas.

The Department of Homeland Security rule change expands the number of assistance programs that can qualify someone as a public charge, adding food stamps and public health insurance programs, among others.

“With this filing we are fighting to prevent the public charge rule from taking effect and harming our communities,” Bitta Mostofi, commissioner of the Mayor’s Office of Immigrant Affairs, said Tuesday.

“This rule is an assault on the healthcare and well-being of not just immigrants, but all New Yorkers,” said Mostofi. “Confusion around public charge poses a significant risk as many immigrants who are not affected by the rule may avoid seeking the help they need due to fear.”

The city’s filings are in support of a federal lawsuit opposing the rule change, which was filed in August by New York Attorney General Letitia James and the attorneys general of Connecticut and Vermont. It argues the revision is unconstitutional and ignores “a century’s worth of case law.”