Oklahoma Attorney General Nominee Vows to Sue U.S. Over Illegal Immigration

Former state Sen. Scott Pruitt -- a candidate for Oklahoma attorney general -- plans to announce on Thursday that, if elected, he will sue the federal government for all expenses his state incurs as a result of illegal immigration, Fox News has learned.

The campaign promise comes on the heels of a tough, new law aimed at cracking down on illegal immigration in Arizona and is sure to rile federal officials who have harshly criticized the Arizona law.

Pruitt, a minor league baseball team owner, is facing former Gov. Frank Keating's son-in-law, Ryan Leonard, in the primary.

Pruitt plans a promise to "hold the federal government accountable for all expenses the state incurs," campaign consultant Terry Allen told Fox News, including in jails, schools, medical facilities and more.

The states do get federal funding to cover these types of expenses, but state officials have long complained that it's not nearly enough.

Allen said Pruitt will claim the expenses amount to an "unfunded mandate" from the federal government, something Congress tries to minimize but often imposes on states.

Fiscal conservatives have long called for a constitutional ban on unfunded mandates, and the recent passage of health care reform legislation is cited as a prime example.

The promise comes as state attorneys general around the country are mounting legal challenges against the federal government, particularly with regard to the new health care law.

Pruitt will make his announcement at a 2:30 p.m. ET news conference in Oklahoma City.

Pruitt was elected to the state Senate for two four-year terms beginning in 1998, and served as Republican whip and assistant Republican floor leader during his tenure in the legislature. He resigned his Senate seat to run for lieutenant governor in 2006, but was defeated in the GOP primary.