A federal court challenge could block Donald Trump's executive order seeking to end birthright citizenship for the children of tourists and undocumented migrants born on US soil. The order, one of the most contentious moves of his second term, seeks to reinterpret the 14th Amendment, which has long guaranteed citizenship to almost anyone born in the United States, and its fate now rests with the judiciary rather than the White House.

Legal challenges have been mounted by civil rights groups and Democratic-led states, who argue the order is unconstitutional and cannot override more than a century of settled precedent through executive action alone. The case is expected to move through the appeals process and potentially reach the Supreme Court, with opponents warning it would strip citizenship from thousands of babies born to foreign visitors and undocumented parents if allowed to stand.