HELENA, Mont. (AP) – Montana’s attorney general said Thursday he is asking the U.S. District Court in Missoula for permission to intervene in a water-rights lawsuit filed by the Confederated Salish and Kootenai Tribes.

Attorney General Tim Fox filed a request to enter the case Thursday. He wants the court to dismiss the tribes’ lawsuit.

The tribes in February sued in federal court to prevent the Montana Water Court and the state’s Twentieth Judicial District Court from deciding several water-rights claims on the Flathead Indian Reservation.

The lawsuit also seeks a declaration that water rights for the Flathead Indian Irrigation Project belong to the United States – not to local irrigation districts or irrigators.

Fox argues in his proposed brief that under Montana law, the state Water Court has jurisdiction to determine water-rights claims.

“Montana Water Court is the appropriate court for these matters to be heard and decided upon, but only after all parties have exhausted every effort to agree on a negotiated water compact,” Fox said in a statement. “Bringing these claims to federal court is counterproductive and could derail efforts to reach a negotiated compact.”

After a least a decade of negotiations, a water-rights compact presented to the 2013 Legislature was rejected, prompting the lawsuits.

Who controls water flowing on or through the reservation and how much goes to farmers, ranchers and others through the Flathead Indian Irrigation Project is at the core of the dispute.

Fox said he hopes the overarching water issues can be resolved by a mutually agreed-upon compact between Montana and the Confederated Salish and Kootenai Tribes rather than litigation.

“We are all Montanans, and we must work to settle this issue by coming together and discussing our shared interests and responsibilities as Montanans,” Fox said. “Ultimately, we need a compact that can pass the state legislature and Congress. I urge all of the stakeholders to spend the coming months focused on constructive, civil dialogue that is informed by facts and not inflamed by rhetoric or expensive litigation.”

The 2015 session is the final chance for lawmakers to approve the compact.

A call to the tribes’ communications director, Robert McDonald, was not immediately returned.