.

The Centers for Medicare and Medicaid Services (CMS) on Tuesday announced a nationwide new enforcement effort to ensure illegal immigrants are not receiving taxpayer-funded benefits through the Medicaid and Children’s Health Insurance Program (CHIP). According to a statement released by the agency, CMS will now be cross-checking eligibility records for Medicaid and CHIP recipients with federal immigration and citizenship databases. A CMS official first reported the move to Axios last week.

CMS will require states to validate immigration or citizenship data for Medicaid and CHIP beneficiaries. If data cannot be validated, CMS will receive monthly enrollment reports from each state on ineligible enrollees. The reports are a key feature of a larger CMS effort to tighten verification systems for Medicaid and CHIP. The federal data checks will be run against databases, including those held by the Social Security Administration and the Department of Homeland Security’s Systematic Alien Verification for Entitlements (SAVE) program.

CMS says the initial enrollment report for the effort was sent on Tuesday, and each state will receive its own enrollment report throughout the month. States are then expected to complete eligibility reviews and report their findings back to CMS. According to CMS Administrator Dr. Mehmet Oz, the reports are part of an initiative to remove “ineligible immigrants” from the programs.

“Our enforcement efforts will safeguard taxpayer dollars and ensure that these vital programs serve only those who are eligible under the law,” Health and Human Services (HHS) Secretary Robert F. Kennedy Jr. said in a statement.

Oz added that the change would strengthen CMS’s position on immigration enforcement for health benefits. “Every Medicaid and CHIP dollar misspent is a dollar taken away from an eligible, vulnerable individual in need of these programs. This action underscores our unwavering commitment to program integrity, protecting taxpayer dollars, and ensuring that these vital benefits are available only for those who are eligible under the law,” he said.

Ensuring immigrants are not on Medicaid and CHIP has been a Republican talking point for years. The Trump administration took up the issue again in Trump’s second term, when it moved to reinstate several campaign-trail pledges to expand and tighten eligibility for Medicaid and CHIP. One of Trump’s first executive orders of his second term, issued in February, instructed agencies to review all federal benefit programs for ways to “combat noncitizen voting and ineligible noncitizen participation in Federal benefit programs.”

CMS further announced changes to benefit eligibility in March, when it expanded its definition of public benefits under Medicaid and CHIP to 44 programs from 31. In each case, the expanded definitions required states to check eligibility for each program.

CMS move comes just weeks after a federal judge blocked a related effort by the administration to limit immigrant access to federal programs. On March 21, U.S. District Court Judge Thomas J. Rawles ruled the Trump administration could not share information about Medicaid and CHIP enrollees with Immigration and Customs Enforcement (ICE). In his order, Rawles wrote that while the court understood ICE’s need for “meaningful access to information relating to unlawful aliens, [they] may not exceed the authorities granted to them by Congress.”

In that case, the federal government was directing states to share enrollee information with ICE to help with immigration enforcement and deportations. As part of the ruling, Rawles also prohibited CMS from enforcing mandatory data-sharing rules contained in the HHS Secretary’s Immigrant Enrollment Verification in HHS Programs policy.

CMS’s announcement today comes as the agency also faces new statutory requirements under a Republican spending package. Passed last month, the package included a provision requiring all states to conduct eligibility verification checks for Medicaid recipients at least twice per year, an increase from the previous requirement of once every three years.

A group of more than two dozen Democratic state attorneys general has since sued the administration, saying the move “threatens the lives and well-being of every man, woman, and child in our states.” The attorneys general, led by New York AG Letitia James, said the move to verify immigration status on federally funded programs would violate residents’ rights to equal protection.

“States like New York have built health, education, and family support systems that serve anyone in need,” James said in a statement last month. “These programs work because they are open, accessible, and grounded in compassion. 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. This is a baseless attack on some of our country’s most effective and inclusive public programs, and we will not let it stand.”

The first enrollment reports are now being sent to CMS, but legal challenges are expected to continue into the foreseeable future. With Republicans in Washington focused on restricting access to benefits and Democrats in states focused on expanding them, Medicaid and CHIP have long been areas of contention in the national debate over illegal immigration and public services.