President Donald Trump on Monday officially shut down the Customs and Border Protection-run app designed to help schedule appointments for people seeking eligibility for asylum, closing off a pathway for migrants at the Southern border hoping to enter the United States.

The CBP One App, used by migrants to notify the U.S. government of their intention to arrive at a port of entry and provided resources, has been shut down by the Trump Administration.

As part of sweeping plans to change immigration in the United States, the Trump Administration has removed functionality from the CBP One app, a US Customs and Border Protection app used by asylum seekers to pursue legal admission into the US along the southwest border.