Cavel International Inc. closed its plant in DeKalb, Ill., last year after a federal appeals court upheld the ban. The company urged the justices to step in to allow the facility to reopen. The court did not comment on its order Monday.

The plant was the last horse slaughterhouse in the United States. About 40,000 to 60,000 horses were there annually, and most of the meat was shipped to be eaten by diners overseas.

Two other U.S. plants, both in Texas, also closed in 2007.