The Colorado Supreme Court ruled Tuesday that former President Donald Trump should not be allowed on the state’s 2024 primary ballot, an explosive decision that the court put on hold until next month pending a possible decision by the U.S. Supreme Court to take up the case.

In a 4-3 ruling, the court found that the leading candidate for the 2024 Republican nomination is disqualified from holding the presidency under a provision of the 14th Amendment and therefore should not be allowed on the primary ballot in Colorado. The decision overruled a lower court decision that Trump could remain on the ballot.

The 14th Amendment, resulting from the Civil War, includes language to prevent people who previously took an oath to support the Constitution from holding office if they have “engaged in insurrection.”

The divided court said Colorado shouldn’t list Trump’s name on the 2024 presidential primary ballot, or count any write-in votes cast for him.

But the panel also stayed its decision until Jan. 4, acknowledging that “we travel in uncharted territory.” If review is sought in the U.S. Supreme Court before that date, the Colorado court said the stay should remain in place beyond Jan. 4. That deadline is one day before the Colorado secretary of state’s deadline to certify the primary ballot.

“We do not reach these conclusions lightly. We are mindful of the magnitude and weight of the questions now before us,” the majority opinion says.

“We are likewise mindful of our solemn duty to apply the law, without fear or favor, and without being swayed by public reaction to the decisions that the law mandates we reach,” according to the opinion.

Before a lower court last month, lawyers made wide-ranging arguments during closing arguments, grappling over the ins and outs of specific language in the 14th Amendment and the extent to which Trump’s actions related to the Jan. 6, 2021, attack on the Capitol amounted to insurrection.

The lower court said Trump’s actions were part of an insurrection and the state Supreme Court agreed.

A spokesman for the Trump campaign condemned the ruling Tuesday and framed the court’s decision as election interference.

“The Colorado Supreme Court issued a completely flawed decision tonight and we will swiftly file an appeal to the United States Supreme Court and a concurrent request for a stay of this deeply undemocratic decision,” said Steven Cheung, a Trump campaign spokesman, in a statement.

“We have full confidence that the U.S. Supreme Court will quickly rule in our favor and finally put an end to these unAmerican lawsuits,” the statement read.

Trump’s campaign quickly used the ruling in a fundraising email, seeking contributions “to fight to keep my name on the 2024 ballot and peacefully defend YOUR right to vote.”

Congressional Republicans lambasted the ruling.

Speaker Mike Johnson, R-La., called the ruling “a thinly veiled partisan attack” in a statement. “We trust the U.S. Supreme Court will set aside this reckless decision,” Johnson said.

In a post on social media, Rep. Elise Stefanik, R-N.Y., said the Colorado justices think “they get to decide for all Coloradans and Americans the next presidential election.”

“This will backfire and further strengthen President Trump’s winning campaign to Save America,” she wrote.

Rep. Byron Donalds, R-Fla., said in a social media post that the ruling was “blatant disenfranchisement of millions of voters from the Colorado Supreme Court.”

One of Trump’s most outspoken rivals, former New Jersey Gov. Chris Christie, also criticized the ruling.

“I do not believe Donald Trump should be prevented from being President of the United States, by any court,” Christie said at a New Hampshire town hall, according to a transcript emailed by his campaign. “I think he should be prevented from being the President of the United States by the voters of this country.”

Another rival, Vivek Ramaswamy, said on social media that he would withdraw from the Colorado ballot if Christie, Ron DeSantis and Nikki Haley did so as well, “or else they are endorsing this illegal maneuver.”

On social media, Rep. Ted Lieu, D-Calif., said he was pleased the Colorado court followed the Constitution, saying the justices “appropriately” held that Trump is disqualified from being on the ballot.

“It was very clear to me that the evidence showed Trump called for and incited the mob on January 6,” said Lieu, one of the House managers of Trump’s impeachment in the aftermath of those events.

The Colorado ruling runs counter to other states such as Minnesota, where efforts to remove Trump from the ballot haven’t succeeded.