That's the warning from the Biden Administration with the controversial Title 42 border policy now expiring.
Title 42 was implemented during the pandemic as a way to stem the spread of COVID-19 by tightening certain border-control and deportation measures.
But the policy is ending as of Thursday.
"We are clear-eyed about the challenges we are likely to face in the days and weeks ahead which have the potential to be very difficult," said Alejandro Mayorkas, secretary of the U.S. Department of Homeland Security.
"Our plan will deliver results but it will take time for those results to be fully realized. And it is essential that we all take this into account."
The Biden administration is set to implement new border and immigration measures. Some will speed up the processing of people seeking asylum but also accelerate deportations.
Under the announced measures individuals who cross into the United States without authorization will be presumed ineligible for asylum, with some exceptions. If removed, they will face at least a five-year ban.
Human rights groups are already gearing up to legally challenge these measures and monitor what will happen on the ground.
"Our primary concern is that asylum seekers will be turned away at the port of entry in violation of U.S. federal and international law," said Nicole Ramos with Al Otro Lado, a bi-national advocacy and legal aid organization serving migrants, refugees and deportees in the United States and Mexico.
The administration says it plans to open 100 processing centers in different countries which would direct people to pathways to enter the United States, Canada or Spain. It will also increase access to the CBP One mobile app which helps with Customs and Border Protection services. Access to the app has proven to be a big challenge to the majority of those seeking asylum.
What do the data say?
The most recent statistics as of March from U.S. Customs and Border Protection show that nearly half of all "encounters" at the southwest border were expelled under Title 42.
Encounters refer to when U.S. officials encounter non-citizens attempting to cross the southwest border of the country without authorization.
The total number of these encounters has increased substantially since a low in April 2020, peaking in December 2022 at more than 250,000 people trying to get into the country. They were expelled under Title 42, deemed inadmissible after seeking lawful admission into the country or were unauthorized entries (both under Title 8).
Most of these encounters over the last few years have been with single adults. By contrast, before the pandemic, more than half of people expelled under Title 8 were families.
How will the end of Title 42 impact these numbers?
Southwest border encounters per day have been hovering between 6,000 and 8,000 for the last few months, according to CBP data. And back in February, a Homeland Security report predicted encounters could rise to 11,000 to 13,000 per day, "absent policy changes."
The U.S. border area with the most "encounters" in March 2023 was El Paso. The number of encounters there peaked in December 2022 but still remain higher than the other key border zones.
Back in August 2021, it was the Rio Grande Valley area that had the most encounters, but numbers there have been dropping.
In March 2023, the San Diego area border had the third most encounters. That area has been increasing since October 2019, hitting its peak in April 2022 but still remaining relatively high.