(Reuters) - California was sued on Friday by the largest U.S. trade group for meat packers and processors, which wants to block enforcement of a voter-approved measure requiring farmers to provide more space for animals being raised for food.

FILE PHOTO: Cattle graze at Rancho Feeding Corporation in Petaluma, California February 10, 2014. REUTERS/Beck Diefenbach/File Photo

The North American Meat Institute, whose members include processors such as Tyson Foods and retailers including Walmart, said enforcing Proposition 12 would hurt producers and consumers by significantly increasing their costs.

It also said the measure, which passed last November with 63% of the vote, was an “overreach” that violated the U.S. Constitution’s Commerce Clause by requiring out-of-state producers to comply with California’s rules or face a sales ban.

“Prop 12 hurts the family on a budget with higher prices for pork, veal and eggs, and unfairly punishes livestock producers outside of California by forcing them to spend millions more just to access California markets,” Meat Institute President Julie Anna Potts said in a statement.

Spokesmen for California Attorney General Xavier Becerra and the state’s Department of Food and Agriculture did not immediately respond to requests for comment. A spokesman for the state’s Department of Public Health declined to comment.

In its complaint filed in Los Angeles federal court, the Meat Institute is seeking an injunction against the sales ban targeting out-of-state veal and pork.

The group’s more than 700 members also include packers and processors such as Cargill, JBS USA, Smithfield Foods and Wegmans, as well as Chipotle, Target and Amazon.com’s Whole Foods.

Proposition 12, or the Prevention of Cruelty to Farm Animals Act, sets minimum space requirements for calves raised for veal, breeding pigs and egg-laying hens, and bans the sale of raw veal, pork or eggs from animals enclosed in too little space.

Calves must have 43 square feet (4 square meters) of floor space by 2020, pigs must have 24 square feet by 2022, and hens must have one square foot by 2020 and be “cage-free” by 2022.

Proponents said the measure would phase out extreme means of confining animals.

Animal rights groups were split. The Humane Society of the United States backed the measure, while People for the Ethical Treatment of Animals opposed it, saying it did not go far enough.

The case is North American Meat Institute v. Becerra et al, U.S. District Court, Central District of California, No. 19-08569.