Maryland federal judge Deborah Boardman on Wednesday blocked President Donald Trump’s latest effort to halt birthright citizenship, citing an earlier judgement from the Supreme Court in June.

Ms Boardman, appointed by former President Joe Biden, issued a preliminary injunction restricting Mr Trump from enforcing provisions of an executive order which sought to deny citizenship to children of foreign parents, including those who were not legal permanent residents in the U.S.

“This court must, once again, preliminarily enjoin enforcement of the President’s most recent attempt to strip the right to citizenship from them,” Ms Boardman wrote in a 35-page ruling on Wednesday.

“A month after Barbara [the Supreme Court Case] came down, the President continued his efforts to abolish birthright citizenship for many Americans…The 2026 Executive Order is almost certainly unconstitutional as applied to the certified class for the simple reason that the Supreme Court in Barbara already decided that the children in the class are citizens at birth,” Ms Boardman wrote in her opinion, describing U.S. birthright citizenship as a “longstanding tradition” and a “right enshrined in the Citizenship Clause of the Fourteenth Amendment”.

White House spokesperson Lauren Bis denounced Ms Boardman as “an activist judge” opposing Mr Trump’s “commonsense agenda”.

“This is just another ruling from an activist judge appointed by Biden attempting to thwart President Trump’s commonsense agenda,” Ms said in a statement. “The birthright citizenship executive order is consistent with the holdings and analysis set forth by the Supreme Court.”