WASHINGTON (AP) — The Biden administration is lifting its requirement that international air travelers to the U.S. take a COVID-19 test within a day before boarding their flights, easing one of the last remaining government mandates meant to contain the spread of the coronavirus.

A senior administration official says the mandate expires Sunday at 12:01 a.m. Eastern time.

The official says the Centers for Disease Control and Prevention has determined that it’s no longer necessary. However, it's unclear whether the CDC will make changes to the vaccination requirement. Currently, non-U.S. citizens must show proof of vaccination prior to traveling to the country.

The official spoke on the condition of anonymity to preview the formal announcement.

The official says the agency will reevaluate the need for the testing requirement every 90 days and it could be reinstated if a troubling new variant emerges.