The US Supreme Court passed a sweeping rule to turn migrants away at the border with Mexico by a five-to-four vote.
The court announced on Tuesday (local time) in Washington that it would deal with the restriction known as "Title 42" in a hearing next February.
It thus confirmed an urgent decision of December 20th.
President Joe Biden's administration wants to repeal the rule.
Republican governors oppose it.
Former President Donald Trump introduced “Title 42” at the beginning of the corona pandemic in March 2020 for “public health” reasons.
According to the provision, the border guards are allowed to reject asylum seekers and migrants across the board.
Hundreds of thousands of rejections have been made since then.
Last April, however, the American health authorities found that the entry ban was no longer justified for pandemic reasons.
Republican governors then went to the Supreme Court to challenge the repeal of Title 42.
They warned of a "disaster" at the border.
The expected influx of migrants will do great harm to states, they argued.
Aid organizations, on the other hand, protested that "Title 42" was used as a pretext against asylum seekers.
In Mexico, those who were rejected were threatened with violence, crime and hardship.
White House spokeswoman Karine Jean-Pierre said Tuesday the administration will make further preparations for the day Title 42 is lifted to lawfully and humanely manage the border.
Congress must pass comprehensive immigration reform.