A coalition of 21 Democratic attorneys general sued the Trump administration on Monday over its attempts to restrict undocumented immigrants’ access to federal health and safety net programs.

The suit, led by New York’s attorney general, Letitia James, comes after several federal agencies announced earlier this month that they would no longer allow unauthorized immigrants to benefit from more than a dozen health and education programs, including Head Start, an early education program for low-income children. Trump administration officials said the changes would ensure that federal benefits were reserved for American citizens.

The states said the changes had already caused significant disruption and that providers could struggle to verify the citizenship status of all recipients. They also said the administration’s actions could result in the “collapse of some of the nation’s most vital public programs” and cause some citizens to be denied benefits if they lack government-issued identification.

“These programs work because they are open, accessible and grounded in compassion,” Ms. James said in a statement. “Now, the federal government is pulling that foundation out from under us overnight, jeopardizing cancer screenings, early childhood education, primary care and so much more.”

White House officials said that many Americans rely on government assistance to get back on their feet.

“When illegal aliens exploit these resources, it is at the expense of Americans in desperate need of them,” Abigail Jackson, a White House spokeswoman, said in a statement. “President Trump was elected based on his promise to put Americans first, and that’s exactly what this administration is committed to doing.”

The Trump administration moved this month to expand the number of programs that qualify as federal public benefits, effectively limiting unauthorized immigrants’ access to those programs.

The Department of Health and Human Services said it would no longer allow undocumented immigrants to benefit from community behavioral health clinics or programs that provide support for mental health and substance abuse. The Education Department said it would end subsidies for undocumented immigrants enrolled in career, technical and adult education programs. And the Labor Department said it would restrict unauthorized immigrants from receiving work force development grants.

Unauthorized immigrants generally do not qualify for federal benefits. They are not eligible for Social Security or food stamps, for instance. Hospitals, though, are required to provide emergency care regardless of a patient’s immigration status, for which they can receive reimbursements through Medicaid. Some states have also set up their own programs to provide certain benefits to undocumented immigrants.

In New York, community health centers and family planning clinics could close if they struggle to verify patients’ immigration status and lose federal funding as a result, state officials said. They also said that Head Start providers have already warned that they might not be able to screen people’s immigration status.

The attorneys general argued that the administration acted unlawfully by issuing the changes without following the required rule-making process. They also contend that the administration failed to consider the “devastating impacts” the new mandates would have on states.

The suit was also brought by the attorneys general of Arizona, California, Colorado, Connecticut, Hawaii, Illinois, Maine, Maryland, Massachusetts, Michigan, Minnesota, Nevada, New Jersey, New Mexico, Oregon, Rhode Island, Vermont, Washington, Wisconsin and the District of Columbia.

President Trump has repeatedly said that federal benefits should be reserved for American citizens, rather than “illegal aliens.” This month, Mr. Trump signed a sweeping domestic policy bill that included measures restricting federal benefits for certain immigrants. Immigrants who are legally authorized to live in the United States, but are not green card holders or citizens, will generally no longer qualify for Medicare, food stamps or subsidized health insurance on marketplaces set up by the Affordable Care Act.

Some of the changes would also affect U.S. citizens whose parents are undocumented. The law would prevent citizen children from benefiting from the child tax credit if neither parent has a Social Security number. Previously, citizen children were eligible for the benefit, even if their parents did not have Social Security numbers.