Another 10 U.S. states are suing the Obama administration over guidelines covering which school bathrooms transgender students can use.

Friday's filing means nearly half of the 50 U.S. states are formally objecting to recent federal guidelines that recommend public schools allow students to use bathrooms corresponding to the gender with which they identify, instead of the gender listed on their birth certificates.

Legal analysts said the latest development increases the likelihood that the gender dispute will wind up at the U.S. Supreme Court.

The new lawsuit argues that the federal government circumvented established law in the recently issued guidelines. The complaint filed in federal court in Lincoln, Nebraska, says legislative history does not support an "interpretation of the term 'sex' as meaning anything other than one's sex as determined by anatomy and genetics."

Nebraska, the lead plaintiff in the lawsuit, was joined by Arkansas, Kansas, Michigan, Montana, North Dakota, Ohio, South Carolina, South Dakota and Wyoming. They follow 12 other states that sued the federal government in May over the same Obama administration guidelines.

The states argue that changes to federal school policies should be left up to Congress, not the White House. The Justice Department has rejected that argument, saying that federal civil-rights laws, which bar discrimination on the basis of sex, provide the legal foundation for the department's guidance.

When announcing the guidelines in May, Attorney General Loretta Lynch said, "There is no room in our schools for discrimination."

The Justice Department's guidelines are nonbinding, but school systems could lose millions of dollars in federal aid if they fail to follow them.

FILE- A sign marks the entrance to a gender-neutra
FILE- A sign marks the entrance to a gender-neutral restroom at the University of Vermont in Burlington, Vermont.

The political battle over transgender bathrooms came into the spotlight earlier this year when city officials in Charlotte, North Carolina, passed an anti-discrimination ordinance including a provision allowing transgender people to use bathrooms corresponding to the gender with which they identify.

State legislators in North Carolina overruled the city with a law requiring transgender people to use public restrooms matching the gender listed on their birth certificates.

The statewide debate entered the national discussion when the U.S. Justice Department said the North Carolina state law violated the federal Civil Rights Act, and declared it could not be enforced. Both the Justice Department and North Carolina have sued each other over the issue.