Asylum-seekers line up to be processed by US border agents at a gap in the US-Mexico border fence near Somerton, Arizona, on December 26, 2022
Asylum-seekers line up to be processed by US border agents at a gap in the US-Mexico border fence near Somerton, Arizona, on December 26, 2022 AFP

The US Supreme Court ruled Tuesday that a pandemic-era measure used since 2020 to block hundreds of thousands of migrants from entering the country should remain in place.

Large numbers of migrants have amassed at the border in expectation of the US policy change, which could force the Border Patrol to register and admit all those asking for asylum.

The 5-4 court ruling accepted a petition from 19 states who said they would be swamped with migrants if the Title 42 policy is lifted and the border with Mexico opens up.

The court said the policy introduced under former president Donald Trump would remain in place pending its ruling on an underlying lawsuit challenging plans to remove Title 42, and that it would hear the case in February.

That could give President Joe Biden's government, which had prepared for a gush of migrants, until May or June before a final ruling comes.

"The states contend that they face an immigration crisis at the border and policymakers have failed to agree on adequate measures to address it," the court said in its ruling.

"The only means left to mitigate the crisis, the states suggest, is an order from this Court directing the federal government to continue its Covid-era Title 42 policies as long as possible."

The ruling gave a respite to Biden's administration, which had accepted a lower court ruling that Title 42 could no longer be used to block people crossing the southwest border seeking asylum.

While the government had prepared with more staffing and more fencing along the border, it was not clear how it would have stemmed an expected surge.

Some 2.5 million people were intercepted while trying to cross the southern US border in the 12 months through November.

While two years ago most of the migrants were from Mexico, Honduras, Guatemala and El Salvador, now more than half come from countries much further away -- Nicaragua, Venezuela, Cuba, Eastern Europe and Asia.

Ballooning migrant numbers at the border pose an increasing political headache for Biden and his Democratic Party, who the Republicans have repeatedly sought to paint as soft on illegal immigration.

Critics branded Title 42 "inhumane," and said it was an ad-hoc immigration plan dressed up as a health policy, but fit for neither purpose.

The measure allows for the immediate removal of any foreigner or non-resident trying to enter the country without a visa.

There is no legal process, or any formal deportation to the country of origin, and a border agent can apply a Title 42 expulsion without the lengthy interview process usually required.

But, unlike a regular expulsion, which usually results in some kind of ban on attempting to re-enter the United States, a Title 42 expulsion comes with no black mark.

Tuesday's decision could give the government, which had prepared for a gush of migrants, until May or June before a final ruling comes
Tuesday's decision could give the government, which had prepared for a gush of migrants, until May or June before a final ruling comes AFP