MEXICO CITY — Mexican President Claudia Sheinbaum on Monday described as “unfair” the decision by the Trump administration to suspend imports of Mexican beef cattle for 15 days due to the detection of screwworm in shipments.

Mexico “has been working on all fronts from the very first moment we were alerted to the screwworm,” she said.

The U.S. restricted Mexican cattle shipments in November after the pest was detected but lifted the ban in February following protocols put in place to evaluate animals prior to entry. But there has been an “unacceptable northward advancement” of the screwworm, the U.S. Department of Agriculture said Sunday. The parasite enters the skin, causing serious and life-threatening damage and lesions. — Associated Press