NEW YORK — Migrant buses rolling into New York City could slow dramatically or stop entirely under a new measure the Biden Administration will implement at the southern border.

The Biden Administration plans to generally deny asylum to migrants who show up at the U.S. southern border without first seeking protection in a country they passed through. The measure, while stopping short of a total ban, imposes severe limitations on asylum for any nationality except Mexicans, who don’t have to travel through a third country to reach the U.S.

 Immigration advocates are outraged.      

The rule was first mentioned in January as part of a wider announcement by the administration to let in 30,000 migrants a month from four countries — Haiti, Venezuela, Cuba and Nicaragua — provided they apply to come to the U.S. and don’t just arrive at the border. In the ensuing weeks, the administration said migrant encounters from those countries plummeted, and they’ve hailed it as a model for dealing with immigration.

Critics of the plan say it will expose migrants to even more dangers.

The measure is almost certain to face legal challenges. President Donald Tump pursued a similar ban in 2019, but a federal appeals court prevented it from taking effect. New Jersey’s Democratic Senators Bob Menendez and Cory Booker both say they are deeply disappointed and urged the Biden Administration to reconsider.

Biden Administration officials expect the rule will take effect when the pandemic-era, Title 42, expires on May 11.