Feb 14 (Reuters) - There will be chaos in the U.S. meat marketplace without congressional action on California's Prop 12 law that tightened animal welfare requirements for pork products sold in the state, Agriculture Secretary Tom Vilsack said during a congressional hearing on Wednesday.

Proposition 12, which requires pig confinements to be large enough for animals to turn around, was passed by ballot initiative in 2018 and was upheld by the U.S. Supreme Court in 2023.

The pork industry has said the law burdens pork producers and has called on Congress to repeal Prop 12 through federal action.

The Biden administration had supported the industry's position before the Supreme Court.

"If we don’t take this issue seriously, we’re going to have chaos in the marketplace," Vilsack said. (Reporting by Leah Douglas; editing by Jonathan Oatis)