Explainer-Title 42 is ending at the U.S.-Mexico border. What is it and what happens now?

FILE PHOTO: Migrants walk between the two border fences as they wait for authorities to request asylum in San Ysidro, California, U.S., as seen from Tijuana, Mexico April 29, 2023. REUTERS/Jorge Duenes

WASHINGTON (Reuters) - The United States is getting ready to lift COVID-19 restrictions that have blocked migrants caught at the U.S.-Mexico border from seeking asylum since 2020, a major policy shift with humanitarian and political implications.

WHAT IS TITLE 42?