The lifting of this policy, dubbed "Title 42", was contested by 19 American states, which feared an influx of migrants at the border with Mexico.
In March 2020, the government of former President Donald Trump activated this health system to be able to expel without delay migrants without residence permits arrested at land borders, including potential asylum seekers.
This expulsion measure is immediate, does not allow legal recourse and does not provide for automatic return to the country of origin.
Rare exceptions are provided for, for certain nationalities such as Ukrainians since the invasion of their country by Russia, or for unaccompanied minors.
Human rights activists and experts consider it a violation of international law.
They consider in particular "inhuman" to prevent a potential asylum seeker from formulating his request in this sense.
For them, the current system only encourages migrants to cross the border illegally and to take ever increasing risks to get there by crossing hostile deserts or rivers conducive to drowning.
"We continue to challenge this horrific measure that has caused so much harm to asylum seekers," said attorney Lee Gelernt, who was arguing against the proceedings on behalf of the powerful civil rights group ACLU.
"Title 42" has been the subject of several separate court battles.
A court of first instance, then another of appeal, had pronounced in favor of its repeal.
In anticipation of this potential lifting, several municipalities on the southern border of the United States had begun to install fences and fences.
Many migrants have been waiting around the border for the past few weeks, hoping to be able to apply for asylum in the United States.
"Sinking into Chaos"
The measure will ultimately remain in place until the Supreme Court decides on the merits of this case.
It will hear the arguments of both parties in February 2023 and will issue its decision next spring.
That gives the Biden administration a few extra months to prepare for a potential influx of migrants.
The White House took note of the Supreme Court's decision, urging elected officials to adopt "in-depth reform" of the migration system.
During his election campaign, Joe Biden had promised an overhaul of the migration policy, but all his bills are bogged down in Congress.
The Democratic president is struggling for the moment to put in place a sustainable strategy to manage arrivals at the border with Mexico, 3,000 kilometers long.
Clandestine arrivals at the US border with Mexico are currently breaking all-time records, with more than 200,000 arrests in November alone.
Immigration is an explosive political topic in the United States.
The Republican opposition relentlessly attacks Joe Biden, accused of having turned the border into a sieve.
The decision of the Supreme Court was immediately applauded by the Republican camp.
"It will prevent people living on the border from sinking into total chaos," said Texan elected official Tony Gonzales.
The summary of the
France 24 week invites you to come back to the news that marked the week
I subscribe
Take international news everywhere with you!
Download the France 24 app