Federal judge blocks Trump order requiring citizenship proof on federal voter registration forms

However, a spokesperson for the White House told Fox News Digital Trump acted within his legal powers.

"President Trump has exercised his lawful authority to ensure only American citizens are casting ballots in American elections," White House deputy press secretary Abigail Jackson told Fox News Digital in an email. "This is so commonsense that only the Democrat Party would file a lawsuit against it.

"We expect to be vindicated by a higher court."

The judge sided with the plaintiffs - including the League of United Latin American Citizens (LULAC), the Democratic National Committee and the League of Women Voters Education Fund - arguing the Constitution "assigns no direct role to the president in either domain."

The ruling says the U.S. Election Assistance Commission is permanently blocked from adding the requirement to the federal voter form, according to The Associated Press.

The lawsuit will continue as the judge examines other parts of Trump's order, according to The Associated Press.

The order also directed the attorney general to enter into information-sharing agreements with state election officials to identify cases of election fraud or other election law violations and conditioned federal election-related funds on states complying with federal election integrity measures.

"There are other steps that we will be taking in the coming weeks," Trump said just before signing the order. "We think we'll be able to end up getting fair elections."

Kollar-Kotelly previously issued a preliminary injunction in April, and another federal judge blocked the same March 25 executive order in June after a separate challenge brought by Democratic state attorneys general, The Associated Press reported.

The White House did not immediately respond to Fox News Digital's request for comment.

Fox News' Louis Casiano, Shannon Bream and Bill Mears contributed to this report.