Texas and 15 other Republican-led states sued the Biden administration on Friday seeking to halt a new program that could give legal status to hundreds of thousands of undocumented immigrants who are married to U.S. citizens.

Filed just days after the program opened for applications, the lawsuit is the latest in a string of legal actions Texas has led challenging federal immigration policies and powers.

The suit, filed in the U.S. District Court for the Eastern District of Texas, seeks a temporary restraining order and preliminary injunction to immediately suspend the program.

In court filings, the states assert that the program is illegal because it exceeds the discretion that the executive branch has to set policy.

“The Biden-Harris Administration — dissatisfied with the system Congress created, and for blatant political purposes — has yet again attempted to create its own immigration system,” the 67-page court filing said.

“This agency action is nothing less than mass amnesty cloaked in purported executive discretion — a sweeping, last-minute ploy by an administration bent on rewriting immigration laws without Congress,” it said.