LITTLE ROCK, Ark. (AP) — Cherokee Nation Entertainment filed a lawsuit Friday challenging a constitutional amendment Arkansas voters approved this week that revokes its license for a planned casino in the state.

The lawsuit filed in federal court calls for the measure approved by voters on Tuesday violates their constitutional rights and seeks to block its application before it takes effect on November 13. The constitutional amendment blocks a casino that was planned in Pope County.

Pope County was one of four places where casinos were allowed to be built under a constitutional amendment that voters approved in 2018. Casinos have already been built in the other three places.

“Cherokee Nation Entertainment is firmly committed to protecting its constitutional rights, defending its lawfully issued casino license, and safeguarding the significant investments it made in good faith based on the establishment of Pope County’s casino license under Amendment 100 in 2018. “Bart Calhoun, an attorney for Cherokee Nation Entertainment, said in a statement.

The lawsuit is the latest in a costly fight between the Cherokee Nation and the Choctaw Nation of Oklahoma, which had spent at least $30 million combined campaigning over the ballot measure. Last month, the state Supreme Court rejected a lawsuit from the Cherokee Nation seeking to disqualify the ballot measure. The Choctaw Nation operates a casino near the Arkansas border.

“This legal action to try to circumvent the voice of Arkansas voters is not unexpected,” said Hans Stiritz, spokesman for Local Voters in Charge, the Choctaw Nation-backed campaign in favor of the measure. “But we have full confidence in the process that brought issue 2 to the polls. “Arkansas voters have spoken clearly on Issue 2 and we hope it stands.”

Attorney General Tim Griffin called the lawsuit “baseless” and said he was prepared to vigorously defend the state.

The proposed amendment removes authorization of the Pope County casino from the state constitution. It also requires that future casino licenses be approved by voters in the county where it would be located. Currently, the constitution requires applicants for casino licenses to submit letters of support from local officials.

Cherokee Nation Entertainment has said it plans to build a 50,000-square-foot (4,600-square-meter) casino northeast of Russellville, 60 miles (97 kilometers) northwest of Little Rock. Plans also include a 200-room hotel, a conference center and an outdoor music venue.