Sixteen Republican-led states are suing to block a federal program that could potentially give nearly half a million immigrants without legal status who are married to U.S. citizens a path to citizenship.

The coalition, led by Texas Attorney General Ken Paxton, filed suit Friday to halt the program launched by President Biden in June. Court filings argue that the administration bypassed Congress to create a pathway to citizenship for “blatant political purposes.”

“This action incentivizes illegal immigration and will irreparably harm the Plaintiff states,” the suit says.

Under the policy, which started taking applications Monday, many spouses without legal status can apply for something called “parole in place,” offering permission to stay in the U.S., apply for a green card and eventually get on a path to citizenship.

But the program has been particularly contentious in an election year where immigration is one of the biggest issues, with many Republicans attacking the policy and contending it is essentially a form of amnesty for people who broke the law.

Paxton said in a statement Friday that the plan “violates the Constitution and actively worsens the illegal immigration disaster that is hurting Texas and our country.”

The suit filed against the Department of Homeland Security, DHS Secretary Alejandro Mayorkas and other Biden administration officials accuses the agency of attempting to parole spouses “en masse,” which the states contend is an abuse of power.

In a post on X, Florida Attorney General Ashley Moody said her state is challenging the parole in place policy because she believes the Biden administration “is illegally using ‘parole’ in a systematic way to advance their open-borders agenda.”

A White House spokesperson told CBS News in a statement that the administration will “vigorously defend” the policy. 

“Republican elected officials continue to demonstrate that they are more focused on playing politics than helping American families or fixing our broken immigration system. This lawsuit is seeking to force U.S. citizens and their families, people who have lived in the United States for more than ten years, to continue to live in the shadows,” the spokesperson said.

In a separate statement, a spokesperson for the Department of Homeland Security said the policy is “grounded in well-established legal authority, and its purpose – enabling the families of U.S. Citizens to live without fear of separation – is consistent with fundamental American values.”

To be eligible for the program, immigrants must have lived continuously in the U.S. for at least 10 years, not pose a security threat or have a disqualifying criminal history, and have been married to a citizen by June 17 — the day before the program was announced.

They must pay a $580 fee to apply and fill out a lengthy application, including an explanation of why they deserve humanitarian parole and a long list of supporting documents proving how long they have been in the country.

They apply to the Department of Homeland Security, and if approved, have three years to seek permanent residency. During that period, they can get work authorization. The administration estimates about 500,000 people could be eligible, plus about 50,000 of their children.

The DHS spokesperson said the agency will continue to accept and process applications.

Before this program, it was complicated for people who were in the U.S. illegally to get a green card after marrying an American citizen. They can be required to return to their home country — often for years — and they always face the risk they may not be allowed back in.

contributed to this report.