Justices Clarence Thomas and Samuel A. Alito Jr. dissented. A group of Venezuelan migrants had been scheduled to be flown out of the country under the little-used wartime statute, according to people familiar with the matter.

Less than two weeks after the Supreme Court allowed President Donald Trump to use a controversial 18th century wartime authority to speed deportations, the issue has rocketed back to the justices in a second short-fuse appeal with enormous potential consequences.

The case raises questions about the Trump administration's adherence to limits set by the Supreme Court. It carries the risk of a significant clash between the two coequal branches of government and potentially a full-blown constitutional crisis.