A group of Republican attorneys general have brought into the courts a fight over an Obama administration rule over contraception-covered insurance plans at religiously-affiliated employers, calling the policy an affront to the First Amendment's protection of religious liberty.

A lawsuit filed in federal court Thursday seeks to strike down a rule under President Barack Obama's health care law requiring employers like Catholic hospitals and universities to offer insurance plans that cover basic medical care for women, which includes birth control.

Obama has since attempted to quell the pushback from Catholic officials with a compromise allowing the insurance companies to subsidize the cost of birth control so that Catholic employers can avoid covering birth control, which they find morally objectionable.

But the change in policy will be implemented this year, giving religious organizations a one-year exemption from the existing proposed rule being challenged in the lawsuit filed Thursday.

This regulation forces millions of Americans to choose between following religious convictions and complying with federal law, said Nebraska Attorney General Jon Bruning. This violation of the 1st Amendment is a threat to every American, regardless of religious faith.

Bruning, a 2012 contender for the U.S. Senate, is leading the legal challenge to the policy, representing a Lincoln, Neb., nun; a Catholic woman who works for an organization that does outreach on college campuses; two Catholic social service organizations; and a Lincoln, Neb., Catholic high school.

Bruning is joined in the suit by Republican Attorneys General Alan Wilson of South Carolina, Bill Schuette of Michigan, Greg Abbott of Texas, Pam Pondi of Florida, Mike DeWine of Ohio and Scott Pruitt of Oklahoma.

The suit is akin to one 26 Republican attorneys general filed against the Obama administration over the Affordable Care Act, set to be argued before the U.S. Supreme Court in late March.

The proposed rule, which Thursday's complaint calls an unprecedented encroachment on the liberty of the plaintiffs, is already subject of a lawsuit from three religiously affiliated colleges and a Catholic television network.