Washington DC - A Donald Trump executive order critics say could severely restrict the right to vote is facing new legal challenges.

The Campaign Legal Center and State Democracy Defenders Fund filed a lawsuit Monday on behalf of the League of United Latin American Citizens (LULAC), Secure Families Initiative, and Arizona Students’ Association.

The complaint argues that Trump's order requiring proof of citizenship when registering to vote accuses the president of overstepping his authority under the Constitution.

"The Order violates and subverts the separation of powers by lawlessly arrogating to the President authority to declare election rules by executive fiat," the suit states.

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"The Order is an attack on the constitutionally mandated checks and balances that keep American elections free and fair. Through this unconstitutional action, the President intrudes on the states' and Congress's authority to set election rules in an attempt to make it far more difficult for eligible U.S. citizens to exercise their fundamental right to vote."

In addition to the Executive Office of the President, Secretary of Defense Pete Hegseth, Attorney General Pam Bondi, and the Election Assistance Commission are among those named in the complaint.

The lawsuit argues that Trump's executive order will harm the voter outreach efforts and overall mission of the represented organizations.

"This executive order, based on nothing but years of disinformation, is blatantly unlawful and a naked attempt to suppress the votes of targeted communities – disproportionately impacting the Latino community," LULAC National President Roman Palomares said in a press release.

"We are proud to join this coalition seeking to stop the effort to silence the voice and votes of the U.S. electorate – and particularly of voters of color. Our democracy depends on all voters feeling confident that they can vote freely and that their vote will be counted accurately."

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Danielle Lang, senior director of voting rights at the Campaign Legal Center, echoed, "The president’s executive order is an unlawful action that threatens to uproot our tried-and-tested election systems and silence potentially millions of Americans.

"It is simply not within the president’s authority to set election rules by executive decree, especially when they would restrict access to voting in this way."

The Democratic Party filed a separate lawsuit against the same executive order Monday.