President Joe Biden says the U.S. will immediately begin turning away Cubans, Haitians and Nicaraguans who cross the border from Mexico illegally. It's his boldest move yet to confront spiraling arrivals of migrants since he took office two years ago. The new rules expand on an existing effort to stop Venezuelans attempting to enter the U.S., which led to a dramatic drop in Venezuelans coming to the U.S. border. Together the changes represent a major revision to immigration rules that will stand even if the U.S. Supreme Court ends a Trump-era public health law that allows American authorities to turn away asylum seekers.

The Biden administration has been conspicuously silent about how migrants should enter the United States when Trump-era asylum limits end, fueling rumors, confusion and doubts about its readiness. Many expect an online registration system. Migrants have been denied rights to seek asylum under U.S. and international law 2.5 million times since March 2020 on grounds of preventing COVID-19. The public-health rule known as Title 42 was scheduled to expire Wednesday until U.S. Supreme Court Chief Justice John Roberts ordered a temporary hold. The end of Title 42 is expected bring more migrants across U.S. borders.