The Department of Justice is warning Gov. Greg Abbott that it will sue if Texas moves forward with legislation empowering state officials to remove people from the U.S. who they suspect of being in the country illegally.

The new legislation, which Abbott signed into law earlier this month, is unconstitutional and will disrupt the federal government’s immigration enforcement operations, Principal Deputy Assistant Attorney General Brian M. Boynton wrote in a letter to the governor obtained by Hearst Newspapers.

The letter says that if Abbott does not confirm the state will forgo enforcement of the law by Jan. 3, “the United States will pursue all appropriate legal remedies to ensure that Texas does not interfere with the functions of the federal government.”.....

The Justice Department points to a landmark Supreme Court ruling from 2012 that held that only the federal government has the power to enforce immigration laws. Abbott has cast the law as an opening for the high court to reconsider that ruling.

In that case, the high court struck down portions of an Arizona law that authorized police to arrest anyone suspected of being in the country illegally. Then-Justice Anthony Kennedy wrote that the federal government has “broad discretion” in setting immigration policy and that the state could not pursue policies that “undermine federal law.”