A federal judge Thursday blocked a Postal Service regulation that would exert control over mail-in ballots ahead of the midterm elections in the latest setback on the issue for President Donald Trump.

The recently finalized measure would implement a key provision of Trump’s executive order on mail-in ballots that would add a new level of bureaucracy to the elections process, which is typically administered by states.

The executive order directed the U.S. Postal Service to, among other things, track mail-in ballots and potentially reject those submitted by people not on a federal list of eligible voters.

The decision by Boston-based U.S. District Judge Indira Talwani in one case brought by the League of Women Voters and other groups and another brought by a coalition of states means part of the executive order remains blocked for at least 14 days, with time running out to implement it ahead of the November election.

“This rule is a clear attempt by the federal government to interfere in elections it has no power to control,” New York Attorney General Letitia James said in a statement. “Today, a federal court halted it before this administration could wreak havoc on our elections.”

Talwani wrote that the regulation is most likely unlawful because the president cannot insert the federal government into elections without the express authorization of Congress.

“The court finds plaintiffs likely to succeed on the merits of their claims,” she added.

The Trump administration could seek to quickly overturn her decision by rushing to the Supreme Court.

Trump often criticizes mail-in ballots, claiming without evidence that there is rampant fraud even though they are widely used by Republicans and Democrats all across the country.

Talwani noted in her ruling that the administration had not offered “any evidence regarding fraudulent absentee or mail-in voting.”

The government’s interest in “correcting an unsubstantiated problem through likely unconstitutional means is dwarfed by the overwhelming risk of pervasive disenfranchisement,” she added.

Directly addressing the short time frame ahead of the election, Talwani said states “have neither time nor funds” to meet the necessary requirements, including updating election management systems and training staff members.

Based on the evidence before her, states’ compliance with what the Trump administration is asking of them before the 2026 midterms would be “practically impossible,” Talwani wrote.

In a separate decision Wednesday, Talwani lifted an earlier injunction she had imposed that blocked vital elements of Trump’s executive order in the case.

It is a different injunction from the one the Supreme Court lifted Monday in a similar case brought by California and 22 other states. Talwani is overseeing both cases.

The Supreme Court found that Talwani had acted too hastily in ruling on the executive order but did not weigh in on whether the underlying proposal or the Postal Service regulation is lawful.

While the Postal Service regulation is now blocked, a provision of the executive order requiring the Department of Homeland Security to compile lists of eligible voters and send them to states remains in effect.