ST. PAUL — Minnesota Attorney General Keith Ellison says he’s stepping in to keep school milk prices affordable, the St. Paul Pioneer Press reported.

“Milk in schools isn’t a luxury — it’s a staple and a necessity,” Ellison said in a statement announcing an agreement with the Dairy Farmers of America.

The unusual move comes after the Dairy Farmers of America acquired a St. Paul milk processing facility in October 2018 from Canadian dairy company Agropur. Before the acquisition, metro school districts bought milk from that plant and a competing facility owned by Kemps.

Kemps is already owned by the Dairy Farmers of America and Ellison alleged the cooperative essentially had created a monopoly over the local school milk supply. The Dairy Farmers of America denied those claims.

Ellison and the dairy cooperative agreed to an “assurance of discontinuance” that will require the Dairy Farmers of America bid for school contracts and prices be no higher than the 2018-19 school year. The agreement allows prices to be adjusted to “reflect the current milk industry.”

Ellison said the deal would “blunt the anti-competitive edge” the Dairy Farmers of America had created by purchasing the St. Paul milk processing plant.

Most of the approximately 40 school districts affected by the move are in the Twin Cities metro.